Maya, take a deep breath! I wouldn't totally write him off just yet.....
*EVEN* if he did sign up to those groups, I don't think it necessarily is really a true indicator of him and his true values as a person. People "click" on things and don't think about it or take it seriously it all. In fact, I would even be prepared to defend him and say that even if he did sign up to those groups, it is probably more on the basis of never having put serious thought into these issues, rather than being seriously opposed to them. This is not necessarily because he is ignorant, but because the environment he grew up in did not expose him to these issues, and as an adult his mind is pre-occupied with other areas of interest. (Mind you, I have absolutely NO idea what you are refering to, when you talk about tea-parties! What is this? So please read my comment based more on the vegetarian/animal rights issues.)
I can say unequivocally that if I had seen a facebook profile of my husband and his interests, or he of mine, I can tell you - we would NEVER have got together. I mean it!
My husband was vegetarian when I first met him and to be honest, I just could NOT for the life of me "get" why on earth he would make such a choice. He loved sport. I loved classical music. He's tall. I'm short. He's a mathematician. I'm a musican (and pretty crappy at maths). We didn't even have the same political views at the time (I'd say because frankly at the age of 23 I couldn't be bothered at that point informing myself properly about what different parties stood for). I could go on and on about our differences!
What we DID discover, is that once together, we share the same values toward relationships, family, love and commitment and for some unknown reason, we just "clicked". (We also discovered that we both HATE sci-fi and LOVE herbal tea! Oh and we both thought each other was lovely appearance-wise of course!)
As we got to know each other better, I discovered I really valued his personal integrity in terms of vegetarianism (I'd been a ravid meat eater before we met), he learnt to enjoy classical music, I learnt to watch football sometimes on TV without falling asleep and so on. Not all things have meshed though, I'm still bad at maths and he still hasn't a musical finger in his body.
My point is that we are very different and I actually think this is WONDERFUL! Meeting him and being his partner absolutely changed my viewpoint and lifestyle towards not only the consumption of animal products completely, but opened my eyes to a whole different world. I like to think I did the same for him. One reason I think we worked out is because he never, EVER forced his views on me, nor I on him - we just were interested in why each other felt certain ways about certain things.
As such, I think that the time to really "judge" the guy is when you spend time with him and talk to him, not through facebook.