If it is the right kind of frat, then yes, a house can have a threshold.
Let's look at
Revenge of the Nerds. The Alpha's original house would not have a threshold, but the Lambda house would. There was a
real sense of
brotherhood there. These guys would do anything for each other. Sure, there are arguments, resentments, and what not, but it is like that with any other family.
To paraphrase Harry re: Morgan: "He might have been an A-hole, but he was
our A-hole.
Also, keep in mind, that a lot of frats use several rites, rituals, and ceremonies during the course of a year. I'm not talking about the "Thank you Sir, may I have another" stuff from
Animal House, but based on old and well-respected rites such as
. A lot of "secret societies" look to ancient texts, or what was saved from them, as a basis of their degrees, passages, etc... There could be
real power in those rites.
Really, it's just a game and if it helps the story, then have at it!