I don't think USBC would do anything if a complaint was filed.
There are so many illegal balls being thrown nowadays, what would be the difference? I mean by illegal, based on how many balls are rejected at the weighing counter at Nationals. Some of those balls are not brought into tolerance at Nationals so the bowlers go back home and use them in leagues.
And for me, I don't really notice what other bowlers are throwing so if they are doing that, it has been getting by me. Do others on here really pay that close attention to what each bowler is using? I am usually more concerned with my own game or my teammates, so I only pay attention to what lines are being used by the other team, not which balls.