Because they're Notre Dame. It ticks me off too, but their fans and boosters have lots of money to waste on lousy teams and will sell out a bowl game no matter where it is.
Normally, that's true but I don't think a 6 - 6 team would be shameless enough to go to a bowl game, not even Notre Dame. They're an embarrassment and I would hope they would simply try to regroup for next year at this point.