I think its another one of those foods that you need to trial for yourself....I used to have these crisps a few years ago when I followed all green days and they never affected my losses.
I can understand totally where the syns come from though...if I was to eat a 300g jacket spud with beans and cheese(HE A), I would be satisfied, however, if I were to eat a 300g potato made into crisps, I would probably (most definitely) be rooting in the cupboards 10 minutes later looking for more food!!
Treats, about the pork? Pork is free regardless of how you cook it. Perhaps they are assuming we would be cooking it in some kind of oil/fat?