Kind of the way I look at it is that you can't completely divorce the two, but you can be careful. We might not have a major impact, but there's no way we can set it during cannon without interacting with it in some fashion.

For example, all student of the same year, house, and gender seem to share a dorm. If you're a first year boy in Gryffindor then cannon would dictate you share a dormitory with Ron, Neville, Dean, Seamus, and Harry. For girls it would be Hermione, Parvati, Lavender.