I don't eat much meat, dairy and eggs, but I don't consider myself vegetarian or vegan. I guess I eat meat about once a week. I've had a bunch of vegan meals, both homemade and from professional restaurants. I have some vegan family members, so I eat that sort of stuff fairly regularly. While some of those meals are good, I often feel like they're just missing something. And if gluten-free comes into the mix, forget about it. Gluten-free "bread" is not deserving of the name.

Going full vegan would take the fun out of life for me. They don't even have anything approaching a good pizza or lasagna. Can't have nachos. Can't have a proper cake on your bday. No thank you, I'll pass. I'm not saying you should eat that stuff every day, but I want to be able to eat "unhealthy" food now and then.

Even most "regular" products you can buy contain things like lactose, so you're pretty much limited to expensive specialized vegan products. Besides, I'm not convinced that any radical diet is the only healthy way to eat, and some of them are actually quite unhealthy if done wrong. I'm more of an "everything in moderation" kind of guy. In fact the more miraculous claims around some diet, the more skeptical I get. Also, the "holier than thou" attitude that some vegans have really puts me off. Same reason I'm not fond of France.

P.S. Sometimes I go through weeks or months of eating no meat/dairy/eggs and effectively eating vegan. Other times I eat non-vegan more often than usual. I don't think I've noticed any clear effect on mood (or energy levels for that matter--a claim often made by vegans).