Maybe my experience was different, but I know plenty of people (not a majority, but a fair few) who didn't have dates and no-one ever bagged them. All about having respect for other people's wishes I guess.
Spilling noodles on yourself is a mistake though, not having a date is on purpose and deliberate.
I feel like I need to clarify my first statement and come to paul's defence here... the reason why imo, generally, you need to bring a date is because that is part of the point of a formal, at least imo. Everyone brings a date, and it's like your first foray into classiness after a childhood previously encompassed by goon sack's at parks (just kidding

). I've been to two formals (not MHS yet), both co-ed, and everyone had a date - so maybe my perception of it will be different after I go to my own formal.
As far as getting shit for it goes, I duno, it really depends on the person. I don't think that should be your biggest worry, but everyone's friends are different and it really depends on your relationships with people... if one of my close friends tried really hard to get a date and couldn't find someone, then of course I wouldn't give them shit. That said, if they simply "ceebs'd" bringing someone and decided to rock up alone, I'd probably bag them a bit but they wouldn't care since they made that choice <= see where I'm going with this? In the end, do what's best for you

, but if you can bring a date who you're friends with I think you should.