Much of it is just a continuation of jokes and memes about FFXI's similar tarutaru race, where it was there it was more just humorous banter about their out-of-proportion body shape (their heads were as big as their bodies - believe it or not lalafell are actually better proportioned), and even then it was mostly limited to jokes about eating taru and 'tarupunting' (aka 'taruball' - you have exactly three guesses as to what part the taru played in that! ).

To me it was (mostly) never mean spirited and was all in good fun (and taru gave as good as they got, I remember one time in Lower Jeuno after one such player shout out about eating taru, a taru player responded "Don't eat more taru! Eat more GALKA!!" (galka are FFXI's counterparts to roegadyn).

So all the jokes about lalafell being food and stuff is mostly just a continuation of FFXI taru jokes (it also doesn't help that the very word 'lalafell' sounds like an actual food which is ironically ball-shaped.... ).