Art review: Royal Scottish Society of Painters | Society of Scottish Artists | Visual Arts Scotland

I am no advocate of the supremacy of the market. Nevertheless, the art market matters because, unlike other art forms, visual art has a material value. Like stocks and shares, it can gain value or lose it and end up worthless. If you buy a work of art, you are buying into a real economy. One unforeseen consequence of public subsidy for the arts was, however, to create a separate, quite different economy in which the private buyer had no part. This was compounded when people with more money than sense started to buy the kind of art no ordinary mortal could house or would ever want to. Self-consciously distancing the taste of the wealthy from that of more ordinary folk, this further split the market.

The Scottish National Gallery of Modern Art has tended to side with the wealthy in this, further undermining confidence in the kind of art that you or I might actually want in our houses. Nevertheless, that is also what most artists want to produce. Edinburgh has the largest gallery community outside London, but finding exposure to the market is still a real problem for a great many artists. That is where the exhibiting societies come in. They are co-operatives where producer meets consumer and, although they take a commission, there is no middleman. That's better for both parties, but it also fosters diversity and gives independence a chance.

These societies play a vital role in the economy of our art, but they are in trouble. When Timothy Clifford mounted his putsch against the Royal Scottish Academy (RSA) and dislodged it from the building that by Act of Parliament bears its name, the Academy did at least keep its right to hold its annual exhibition there. The collateral damage from this attack was severe, however. Three of the principal exhibiting societies, the Royal Scottish Society of Painters in Watercolour (RSW), Visual Arts Scotland (VAS), and the Scottish Society of Artists (SSA), had always held their exhibitions in the RSA. The space was provided as a public service and they paid a peppercorn rent. Having taken over the RSA and expensively refurbished it, the National Galleries of Scotland could no longer continue this arrangement and now feels obliged to recover the costs incurred when it is hired out. They are considerable.

This year all three societies have joined together and the rent alone, apart from their other overheads, is in the region of 30,000 for seven weeks. Because of the demands of selection and hanging, only a month of that period is actual exhibition time. Their only income is from sales at their annual exhibitions, there is no public money. None of the societies can afford this kind of rent on their own, nor can they even do so together. About ten years ago, anticipating this crisis, the three societies formed the ESSA (Exhibiting Society of Scottish Artists), an umbrella organisation to raise funds to help meet these new costs by holding auctions and by other means. It is a struggle to raise enough, however, and the future is uncertain.

All three societies have retained open submission – all the more important as the RSA is proposing to abandon this vital principle – but they do remain distinct. Each has its own submissions, selection and catalogue and its own share of the space. This year, the SSA and the RSW have split the upstairs down the middle and VAS has the whole downstairs. Between them they are showing more than 600 works.

Although this is a market place, not everything is saleable. In the SSA, Gerry Smith's Intervention II is composed of coins frozen into melting blocks of ice. You couldn't do much with that in a domestic space, nor could you with Fiona Hutchison's rather beautiful Sea Papers: Ocean, made of curls of blue and white paper on a heap of salt (at least, I think that's what it is made of, but none of the catalogues gives that kind of information).

Still in the SSA, I would certainly make space for Julie Millar's Rites of Passage – Please Lower Your Head. It is a small door, its flat panels replaced with little hanging panels painted like the wings of an altarpiece with figures against gold in front and grisaille behind. Gerald McGowan's Saturday Before Last is also a composite of little pictures, all of people doing casual things.

Generally the work in the SSA is very diverse. Roland Fraser's 4x6, for example, is a kind of solid collage of blocks neatly cut from scruffy old painted wood, while Georgia Murray's Beautifully Infinite is a naked female mannequin splashed with paint. Each year the Society also invites artists from the annual degree shows. Harriet Lowther's The Big Thank You Project, a star of Glasgow School of Art's show last year, is a collection of letters she sent out to big firms thanking them for their products, and the startled replies that she received.

Given its name, the RSW should be all watercolours, but it has long since ceased to be so circumscribed. Nevertheless, there are some classic works in the medium – Jack Knox's lovely Artichokes and Asparagus, for instance, Ann Ross's big and spacious Arid Lands, Stephanie Dees's Edinburgh Garden, or Ann Patrick's vivid flower still-life, High Summer. David M Martin's charming little Landscape with Moon seems to be an oil painting, but Black Cloud by Jenny Mason is very much a watercolour.

Philip Reeves is showing in both the SSA and the RSW. His Dawn in the RSW, a little collage touched with watercolour, is exquisite and his collage relief Strata with Quartz (also in the RSW show) is calm and grand. A modern master, Reeves is a good example of why we need these group shows, not just for the market, but to keep up with what our artists are doing. You hardly see his work anywhere else. You certainly won't see it in the national collection where, underlining the side it has taken in the split art market, he is one of a good many conspicuous absentees.

Unlike the other two, VAS always has a big craft element. This year there is jewellery and some very fine furniture – a beautiful sideboard by John Galvin, for instance, a satisfyingly solid looking oak chest by Sam Chinnery and an elegant black lacquered chair by Joachim King. There are some good ceramics, too, including a massive blue pot by John Maguire and an intriguing cube of ceramic cubes printed with a seascape by Myer Halliday. A series of reflections on life in the Western Isles – crocheted fish, knitted sheep and golden lobsters – by invited artist Deirdre Nelson, is a delight.

Henry Kondracki, one of the finest painters of Edinburgh's streets, has gone to London to paint a big picture of Piccadilly. Sue Tait's Posy is very painterly, while David Ralston's Untitled, a granite sphere with teeth, is uncompromisingly sculptural. So is Green Venus, a torso made of polished green stone, by Tom Allan. Paul Furneaux's Sea Mountain, a composition of three delicately painted objects, stands satisfyingly between painting and sculpture.

There are quite a few works in all three shows that are not much more than wall furniture, but there is much else too. We would be a great deal poorer if the exhibition societies were allowed to go to the wall.

• All three exhibitions continue until 18 March.