I think ship is perfectly defensible - and yeah, I think that's a fair reason. People can't help but be interested in relationships - I can't watch shows that are all about the action (on the other hand, I don't generally like shows that are all about the relationships, either - can't stand soap operas).

And anyhow, it's there, whether we write it or not - "I care about her, a lot more than I'm supposed to," etc.