It's not for 'pointless for publicity'. Is your graduation just for publicity? You will receive your diploma no matter what, despite the ceremony. Isn't there something you have dedicated and sacrificed for years to achieve? I find it odd that you haven't being that you have an LOA. It is a grand moment of celebration, a culmination of all the years of sacrifice. I couldn't be prouder of those kids, or the ones that compete at the state level in choir, band, debate...or the kids that achieve National Merit awards for academia. It's the same principle.
I saw your post earlier about your beliefs towards athletes. Maybe you do have stereotypes about athletes and this is clouding your opinion. But I can tell you that someone who has earned a scholarship as an athlete has worked harder and self sacrificed more than you can ever know to get there.