Yes, I've often thought that someone else looked very similar to me but never identical and it's the same with similar thoughts too. Don't you think that it makes us unique in a way then? We're all unique because we're all so different which is why I disagree with the word "normal". There is no such thing as normal. As you mentioned though, that mindset soon gets brushed under the carpet as we get distracted by daily life. It's also nice to sit back and appreciate life for what it is sometimes.
Occasionally, I've wondered what it would feel like to be someone else, do they see the world differently to me? How do their minds work? I feel I'm making a fool of myself if I'm the only one who has thought that way, ha.