I recently got dragged onto our Handicap committee at the club. No one really cares about the GHIN until someone wins a couple of the bigger tournaments. There are a handful that always seem to keep high handicaps and then always go low in tournaments. Once is fluke, but 3 times and you're getting looked at. A few people were banned from tournaments and others get their handicap "adjusted".
Then we have they guys that everyone wants to play against, but no one wants to partner with in tournaments. One of the guys in my group is like that. Years ago he probably was no more than a 12, but now he's a 19 and really should be a 24. He won't post any score over 95 and is only a 19 because some of us will post his scores and so will the tournament committee.
Maybe because I'm cheap, but I don't understand why you would want to lose money every round because of a vanity handicap. I don't like sandbagging, but at least that makes sense to me.