There are quite a few English universities which have a house-based system. They're usually the more distinguished, older schools, though, like Oxford and Cambridge.
The long and the short of it is that Hogwarts in the game is a university-level educational institution. This is Word of God, and I believe that it's referenced in the game - though I couldn't tell you where for sure. As you can no doubt tell, some changes have been made to the HP timeline and lore from the books. For instance, Voldemort never met Professor Quirrell in the forests of Bavaria, so he's still dead/a wandering spirit. Some other events have been changed or happen concurrently.