You must be visiting too many porn & crapware sites then, because my experience has been distinctly different from yours.
Of course, you're mostly blowing hot air, because as by your own admission you have everything blocked anyway - you don't see any of it in the first place.
I've never had anything silently installed by flash or anything else on my browser. I got bitten a by search bar once, but only because I stupidly installed some shitware off SourceForge (RIP). It was hardly a surprise.
You're also highly unlikely to see any adult ads on any reasonably frequented gaming site. If you'd worked with ANY commercial sites yourself in the past DECADE, you'd know that.
With the exception of, again, adult & crapware sites, all advertising is now targeted - it's more profitable for the client, it's more profitable for the advertiser, it's more profitable for the site & it's less annoying to the user. And the base line for targeting is aiming at that particular site's audience. So no, you're not going to be finding any adult content on kids' sites.