I was rewatching, and suddenly right at the beginning of "Laundry Day" it hit me. It's not just a convenient place for a berd to develop a crush on a girl, nor is it just an easy Cheetos joke. The setting itself shows how fundamentally different Billy and Penny are.

Billy is always looking for a quick fix to get him to the next stage, at which he will STILL have no clear goals. Even if he DID rule the world, he has no clear goals or solutions.  Even when he's just fantasizing about the freeze ray, it gives him time to… say what he could be saying already, except that unfortunately it is not a "Give Billy Ideas" Ray. Also, he considers laundry to be mindlessly boring drudgework, with the possible exception of Penny's underthings.

Penny, meanwhile, is FINE with slow steady progress. Even when getting blown off by people gathering signatures for something hugely important to her, she still seems to maintain a sense of humor even in the fsace of rejection. Even when Hammer gets her the shelter, she knows it's just great progress, not a happy ending. There are still many places that don't have that shelter, and even helping those who DO make use of it will still be a fulltime job that often fails. And.. rwlated to this difference between her and Billy… Penny has no problem whatsoever with having to keep doing laundry.

Penny is about working constantly to make things better at best, or failing that to at least keep them from getting worse. Billy thinks that there's some kind of Good versus Evil game, that if he just wins he'll somehow blinder into Utopia.

It didn't click in until I was registering just now, but also… even Penny's name shows the difference. One penny doesn't change the world, but enough of them can buy anything.