My best friend is the same, we often laugh about the fact that she rarely does and I always do wear panties, lol.
Takes me back to my HS days, when I was frequently a member of a group of friends (about 6 to 8 of us both guys and girls) who went to the local Little Art theater for their weekly X rated films. Needless to say, wearing underwear during such features was quite binding, so usually avoided the underwear. As the poster had posted, if your jeans have a zipper, it's a good idea to wear underwear. The usual position was to put your feet up on the back of the seat in front, and enjoy the show. One evening, my zipper had come open, and it was me that provided the girls in our group the better show, though I was unaware of that fact at that moment. Soon realized that the giggles and whispering was not matching the film. Found out later that I'd added about a 20 minute show as I had extended well beyond the open zipper. At the time, I felt pretty humiliated, but also somewhat more popular.
I don't wear underwear regularly, unless there is any special activity or sport where it will be protecting me.
I haven't worn underwear since I was about 10 years old, about the same time I stopped wearing pyjamas in bed, coming from a family that went to nudist resorts it isn't surprising I don't much like underwear, my partner never wears panties at home and only occasionally when out.
Mostly don't wear underwear there are a few places I go to or do I put them on until the activity is over then they come off again usually can't wait to get them off.
Wife and I don't ever wear underwear, and I try to wear as light of clothing as possible to give everyone a hint. I watch women staring at my crotch at times, and even the male Doctor that just performed my foot surgery (maybe he's bi - I don't know). I also like the freedom and my wife does too. She even shoots beavers to others when she can while wearing a dress. We're obviously exhibitionists.