Me and my dad have gone out to lunch and spent the majority of the time discussing how credits should have been done in this game.
Firstly, a new player should start off with 500 credits, enough to but him a few nice clubs, or maybe even one extra nice club, but nothing amazing special. In other words, enough to get him something new, but not something great.
As he advances to Ameteur, he should earn an additional 250 credits, to use on whatever he would like to have.
Ranking to Pro should earn 750 credits and Master should earn 1,000 OR 1,500... not sure yet.
The truth is, 50 credits is not near enough, and if people want to spend their money on a great game, they will.