My school is one of the first schools to do the formal. We do it about 1 and a half weeks before grad.
I took a friend of mine who was 1 year older than me. She is really pretty and a good friend of mine, and a lot of guys in my year (I go to an all-boys school) came up to me asking who she was (kinda awkward, some were even flirting ffs). We danced a lot and agreed it was quite a fun night. Also, I didn't feel the need or burning desire for any afters.
At the time, in my mind, I actually looked down to guys who didn't even bother consider taking a formal partner. I felt really awkward at the table I was sitting at; there was 8 guys and 2 girls. Even when I wanted to dance just with my formal partner, there had to be desperate friends of mine that would join us out of feeling socially awkward. I think there was only two instances where I could enjoy dancing with my formal partner alone.
About a week later, I was over holding grudges against guys who I thought had leeched off our enjoyment. Tbh, I'd probably just advise to at least consider taking somebody that you think would make a good choice, otherwise its perfectly fine to go alone and just hang with your mates, just so long as you respect another couple if they want a bit of alone time.