It is extremely poor sports(game)manship to forfeit. WGT has done an excellent job of replicating the beautiful game of golf of which prides itself in etiquette. I wonder if some of these 'quitters' have actually played the 'real' game (my guess is not). In fact, I wonder why WGT have even provided an option. If you commit to a game, you should do the honorable gesture of completing or face a consequence. IE loss of credits, double coins in coins (games), but even better reputation. One could then choose to reject a game against a player with a poor reputation as in past versions of WGT, in fact I wonder why WGT removed this.
You could see a players reputation (not there stats etc) before excepting ta challenge.