No, there are all sorts of very specific and sometimes tragic cases like "who is allowed at the bedside of their dying spouse in the hospital" where official recognition matters. The AIDS crisis produced a number of those incidents, but it's also happened to straight people as well that if you're not officially married you may find your partner's family having legal rights which you don't.
So, to sum it up, straight people marry so that one can not run away easily, and gay people marry for increased closeness? :-) In any case, this subthread was about the inequality between straight couples, so...
Well, as I am not married, this would also apply to my spouse and I. However, I dont feel like this is reason enough to marry, in fact, I never even thought about such a specific case. Death is painful, and likely will not go down as planned, so no reason to worry. See, not a gay marriage specific problem, just the way it is for unmarried couples.