Exposing myself at fast food drive through

TL;DR (Too Long; Didn't Read) - Not normal, I approve, and you might cause some trouble.

My current personal opinion, skewed by being an emotional young male? I like your carefree, slightly-crazy attitude. It's almost like a cheesy porn scenario come true, and I'm sure many folks - both male and female - would/do secretly enjoy it. And plus, how much are people actually seeing?

My proposed objective reality, based on facts and experience?
It's possible the people at the drive-through think you have a mental illness, which may explain the friendliness. Do you acknowledge the exhibition to them?
Porn scenarios feel very different in real-life, ESPECIALLY when in a relationship. It's possible you are sending some men into therapy. If one of them has OCD, then it's basically guaranteed.
If it's women, and you are even remotely sexually attractive, then you could very easily be triggering some body image issues, jealousy, etc (saying this as someone who struggles with these issues).
Plus, it's illegal, called "indecent exposure".

A bit of a combination of objective and opinion?
Sounds a bit like Histrionic Personality Disorder, which is kind of awesome. Exhibitionist behavior, uncomfortable not being the center of attention, rash decisions and getting into risky situations, overly dramatic, easily influenced by others, and pride of own personality, viewing any change as a threat, among other things.