Yes, in Denver in 1993. Someone hired a plane with a banner that said "Use Birth Control" to fly over the stadium. Its just the same kind of desperate-for-attention crowd who protest topless against meat and do other publicity stunts.
Vince, I think the original writer meant has there been a problem in the past with large numbers of kids engaging in sex at these gatherings. I was wondering the same thing myself, and why these dissenting Catholics thought there was a 'need' for their services. My guess is that there would NOT be a need, but these folks just want the publicity.