Been vegan for 8 years. To me it's just one link in the whole world-consciousness thing, which includes both reducing impact on the earth and treating our animal friends with respect. The current trend of factory farms is detrimental in so many ways.
I've noticed that activists of all sorts seem to focus too much on their one cause, and don't take into consideration the interrelation of all things. Choosing to bicycle and living a veg*n lifestyle are just two conscious choices that are very close in value. Riding fixed has a simple, spiritual essence involved with it that also parallels the choice of eating lentil burgers and vegan general tso's.
I don't know about other parts of the country, but here in Portland the fixed-vegan-PBR thing is becoming more style than substance. All the hip spots have vegan food now, and more PBR flows through here than the Willamette river. Veganism seems to just be a tool for many hipsters to boost their self worth over all the micro brew swilling, cheese eating, derailleur-pedaling "yuppies". But I'm not complaining- it's a good thing to see since if they have to follow a trend then these at least are beneficial choices to make.
Bicycling and veganism