What's the appeal of shiny pokemon?

I have seen people hack their whole team back in platinum, so obviously even in cherish balls and what not.
Sure you could say because they are rare, but when you hack your team all shiny and easily spotable as hacks when it comes in a cherish ball they immediately lose all their prestigious value.

Some shinies don't even look good.
Vomit green Espeon for example or shit green Dragonite.