Multiday passes are totally standard.

LA locals get a discount, but they need a picture id (maybe?)

You can go to craigslist and people will sell unused portions of multiday tickets, which have to happen within a particular window and, since there is no record on the ticket about what has been used, leave you open to getting screwed.

Maybe there are hotel/park deals? No idea. There are a whole lot of disney-obsessed-midwesterners who run websites out there...