Submission maneuvers if built up wrong during the match kill ratings. If done right it's a great moment of tension(I think Jericho's the most recent king of timing for a submission). Ratings don't matter for a PPV, people aren't going to tune out just because two guys are just laying there/hugging each other(plus you paid for the damn thing), but if there's something else on that's even remotely interesting during a RAW or SmackDown, you could have someone flip channels during a submission hold.
Plus, I don't think I Quit matches should be watered down like that. Obviously not every one of these would be an I Quit match but they use those very sparsely and it's a nice card to pull out of the deck once every year or so.