I can understand the rep thing. The reps are, ultimately, frivolous though. The rewards are largely lackluster. The no flying thing wasn't that big a deal to me, except when I had to take a stupidly long FP.
It's not about how good the rewards actually are. I went through a lot of pain to get my professions on my Priest to max level (tailor / enchanting). The MoP part was ridiculously easy, everything else wasn't. So I want to be able to actually make something meaningful with that. Doesn't need to be BiS, but I want to be able to create something useful. Right now I've got one set of green iLvl 390-ish gear for tailoring with largely random stats and a selection of PvP items that are freakishly expensive to learn. Oh, and I do never play PvP. Which means that my Tailoring is just about totally and utterly useless without those reps. Could have gone Alch and had the same bonus and better utilities for a lot less pain.
The flying thing I ranted about yesterday, don't want to warm up that discussion. It bothers me to no end, especially because it's a totally arbitrary hindrance. That's about it.