I personally might initially feel a bit miffed at not having meat but I would understand and completely respect your decision to not serve any meat.
Also, like you say, some Italian meals don't contain meat and as a meat eater I don't feel like I'm being 'short changed' when I eat them. For example, you could start with a bruscetta, then have spinach and ricotta tortellini in a sage and butter sauce, then tiramisu. As much as I like meat, I would be completely thrilled if something like that was on the menu!
Hope this has made sense! Basically what I'm trying to say is that, while I like meat very much and eat it with most meals, I would happily go without and, knowing your beliefs, would appreciate your decision.