They seem to still eat some version of milk and eggs from plants or plant like animals, so I've come to think what they eat was more fashioned by where they live more than anything
. Besides, it is hard to hunt little animals (or want to) if nearly all of them can talk to you o.o
Gobo : Okay little cocoming, you knew this was coming...
Little fuzzy animal: Don't eat meeeee ;.;
IMHO Fraggles seem to be on the foodchain somewhere next to mice and birds by the way they live...
But then, if they are viewed like humans in history, they sort of give the feeling of hunter gatherers that just started to settle down but haven't started to farm for themselves...