Wrestling is literally a societal safety net. There are people in the hardcore feds and the independents that would be in jail if they weren't in wrestling. Shit, weren't there two guys on the old ECW roster that eventually got charged for murder?
In a lot of ways, if it weren't for wrestling, tons of the people we know about would be in jail or worse. Its either wrestling that allows you to travel, beat people up, get paid, do drugs and party with your friends, or you're we're all paying for their jail cells with our tax dollars. What sounds worse? I mean, clearly not every wrestler is going to make it to the WWE.
Another thing is just how cheap wrestling is to produce. If you're going balls out, a good pro wrestling is what? Six, eight grand and change? You can literally set it up anywhere. A few belts around $500 each? And there's also an innate desire in people that either love pain, love being athletes or are just good in front of crowds. Wrestling attracts an immense variety of people. You build a ring, people will come and get bumped around in it and others will come for the spectacle and watch it for nothing other than its happening. It is entertainment for the lower classes. Rednecks and hillbillies made it famous and popular first. You talk to any wrestler that's worked in the south and they'll tell you; no teeth, barefoot kids, bloated potatoed meth addicted women telling you that you're going straight to hell cause you're the bad guy. Wrestlings complexity is so simple that anyone can get it and of course, the dregs and crazies come crawling to it.