I've been reading an old book in French by a writer called Henri Chevalier and writing about snail farming to update my booklet for would be snail farmers. It's fascinating to look back at what was written a few decades ago and compare it with the situation now. Chevalier hardly mentions Helx aspersa maxima which seems to be the main variety that people want in the UK.
He refers to it in passing as a giant race from North Africa and then moves on to talking about 'l'escargot petit gris' which is his main topic. He waxes lyrical about Burgundy snails (our Roman snails: Helix pomatia) and has some very rude things to say about the small snails eaten in Spain in what he described as a vague tomato sauce!
I would say that the snail farming market now is in a state of dynamic change. When I first started it seemed fairly fixed - maybe that was an illusion but it felt as though there were a few farmers in the UK, a few in Eastern Europe and lots in France. I was aware of the markets in Spain and Italy and gradually became aware of snail farmers in Greece. Now I get enquiries every week from snail farms in Poland, Bulgaria, Greece, Cyprus and all sorts of other countries. They nearly all tell me they are about to start producing tons of snails and have only just started looking for who is going to buy them. That does seem like the wrong way round to me! The first rule of starting a business surely is to establish if there is a market for your product otherwise you could be in for an expensive disappointment.