I think it is laziness. Vegan is the big thing, so let's jump on the bandwagon without bothering to do any research or think it through. It's also treating the people she tells about it like idiots. I am not so sure she's the dimbo she tries to portray...
Thing is, not that I am vegan, but I have observed that people evolve into veganism. Their concerns for animal welfare, the environment, being intentional in their choices means going vegan is a logical, inevitable step. It can influence whether they stay at, or leave a job, what they wear, where and how they live and then also the food. I just don't think CH did any homework before opening her mouth. Just the usual attention-seeking, I'm afraid.