Back in the day...the military didn't supply 'in the field' hearing protection. Only hearing protection that was provided was at the range and for qualifications stateside. Back in the day.......you got cigarettes in with your C-Rats......many times cigarette butts picked up off of the ground sufficed as "hearing protection" for those who wanted it. One thing you cannot do is wear ear plugs when you need to hear. I thank the Good Lord I still can, and after many years working jobs that fall under OSHA control and workplace awareness........amazingly enough my hearing has actually improved steadily over the last five years.
My opinion? Many think about the home defense experience.......you don't actually want to sleep with earplugs now do you? Yeah....some do...but how are you going to hear the glass breaking or the dog next door? Then there are those that fire a shot from within a more confined space such as a vehicle. My thoughts? Maybe...just maybe one should experience firing off a shot without hearing protection just for the simple experience. I know.....this could be unhealthy in ways, but it may very well also be a good experience. One shot? I personally don't see the harm, and you will heal. Being stupid about it means doing it repeatedly. Being behind a 22LR isn't exactly a statistical point to base your question on either IMO. Depends a lot on whether it's fired indoors or under cover etc........ Regret? Please define at this point and exactly how I should regret what I've done in the past and under what conditions. I have however done plenty of 'stupid' things in the past. Once in a while I end up crossing items off the stupid list and listing them in the good to know list.