You're not being stupid at all. When Lexi was a few months old I bought her a collar and a pretty sparkly tag. I was concerned about the tag being too
heavy for her neck so I asked the vet. She looked at and said 'No, it'll be fine'. That wasn't good enough so I actually had to put it in her hand so she could
feel the weight.
She was so patient, but I can only imagine what she was thinking. I was afraid the weight would cause back or neck problems. The tag was the tiny one, about half the size of a rabies tag!
So, yes, she wears a collar with her ID info on it. She's never outside alone so I don't worry about it getting hung on something.