would be a great shame for the humans off course, but the girls would certainly have a great day together, this is what counts

They probably rate Earth as 10/10.
Total freedom, lots of toys to play with and no one else to bother them but tiny funny ants, the perfect nudist beach.
They don't really think about the destruction their cans cause, they already know Earth is as fragile as sand castles

They probably think of Earth as a pretty nice play to spend an afternoon in, lots of toys and privacy!
They will definitely leave their trash there, they don't really care about the trash at all, they just destroyed several cities just to have a nice afternoon after all