Glad to hear somebody's vegan here! I'm mostly vegetarian, but I sometimes get off the leash...if you know what I mean. Not particularly proud of myself, but I believe that I'll get there eventually.
Trained Snickers for bit today. More like re-training actually, as he was introduced to it too fast and too heavy, and had learned that he has to avoid the bit at all cost. So today he was just to walk and trot along me wearing a bridle and a bit - I didn't lead him, just to let him feel more secure - and he got lots of praise when he chose not to gnaw on the bit, but to just accept it. Then he had to yield a bit of pressure, and that was all for today. I don't think that I will start riding him with a bit daily, but I do believe that it is beneficial for a horse to learn that a bit isn't going to kill him. Still, I prefer bitless for my daily training.