I know I got braces back several years ago because I was unhappy with mine. I don't think someone absolutely has to change whether their teeth are crooked or not, unless they're uncomfortable with it themselves.
Hmm...I think it could be down to a couple of things. Symmetry for one. A lot of the time people who are considered "attractive" have very symmetrical features.
Also, could be down to classim, if unconsciously. Because wealthy people would be able to afford expensive dental care.
I am okay. Thank you - that moustache is the real star of Poirot tbh. xD
Yes is a sad thing when it comes to that.