Chow. I think their problems are a little more... existential in nature.
The problem here is that the group itself is formed under a false premise. Organic/natural foods aren't intrinsically better than conventional or 'mass produced' food. You can think it tastes better as a sort of placebo effect, but nutritionally, an organic/natural version of a conventional food is the same. Asking people in this country to pay more for their food is pretty insulting and shows a complete lack of understanding about economic development.
Much of why we spend so little on food is because we have so much more money and spend it on other things, so as a percentage, we spend less on the food. There's not a lot of people buying Xbox 360's and cars and flat screen tv's in Sub-Saharan Africa. And many people there grow their own food, not because they're hip and socially conscious, but because they'd starve otherwise. As subsistence level farmers, they HAVE to decide how much food they need to sell instead of eat. Their incomes are practically non-existent.
Like most foodies, the Slow Food movement meant well, but were misguided, misinformed, and generally uneducated about food. So what they did was substitute their opinions and feelings in place of facts and then built an institution around them. To shore up that institution, they needed enemies and that's where corporations came in. Most foodies are anti-corporatist, so for them, it was easy to direct vitriol and hatred to any 'big' entity.
Thoughts, feelings, accusations, paranoia, and conspiracy theories support the cause, not science. They see science as part of the 'big' machine that exist only as Yes Men. The problem with this is that any serious critique of a foodie movement like Slow Food shows that that they simply make oversimplified, and unsubstantiated good vs evil populist claims about food.