Because people like them, and everyone has preferences and likings, they sometimes represent the owner of the profile pictures aswell

@ShinyGemsBro and i now have a answer

Cause why not?
If this is an issue, then it seems to be a you problem.
If not, and this is just a question, then refer to @Farewellntchii 's answer

Because yes

@X99STRIKER i saw a a10 on a radar

@X99STRIKER why do you always comment right when i comment?

@Farewellntchii thanks for the explanation