Fair Trade?

As you'll see from our site, Sincarne (http://www.sincarne.net), I purchase my seitán from the local 'Fair Trade' shop round the corner in Plaça de Sant Agusti Vell. I have advertised the fact that this is by far the cheapest place to buy seitán in Barcelona that I know of, and at 2,57€ a chunk, you'll be hard pushed to beat that price. Then today, all that changed. Nipping off round the corner to buy some seitán for lunch, I picked up two pieces as usual and went to the counter. The lady scanned them and up came the price - 3,20€! Imagine my shock. This is an increase of nearly 25% which I find totally unjustifiable. I have written to them asking for an explanation and I await an answer. Perhaps it is my mistake - they may have changed brands (although I am almost certain that they haven't - you can tell the different brands by the texture and appearance of the seitán), or maybe the size is larger that the one they used to sell (the ones I bought today were 290g, but I really don't think they are any bigger than before). So anyway, it appears that market forces affect even the most well-intentioned businesses and perhaps 'Fair Trade' is another nice idea, where the practice is rather different. We'll wait and see, but in the meantime it looks like I'll be paying 25% more for my seitán.
This situation is similar to the price of baked beans at Tot al Born, the supermarket in Pg del Born. About a year ago, they were selling Heinz baked beans at about 70c a tin. So obviously I (and perhaps everyone else in Barcelona) bought all my beans there. Then one day I went to buy some and noticed the price had increased to over 1€ - nearly a 50% pay rise. How can they justify this? They don't have to. Just that if everyone else is charging a ridiculous price for beans in tomato sauce, then so shall we. Is there no justice? Is would seem not.