The virtual equipment mostly acts as an ad for the real equipment. The folks who play WGT are pretty likely, they figure, to buy the goods in RL.
All conjecture about WGT's business model, obviously.
Courses are an interesting aspect. The championship courses generally have nothing to gain from being on WGT, as most of them they are intensely private, snooty clubs with long waiting lists (see: Merion, Oakmont, St. George's et al.). (Bethpage and Saint Andrew's are publicly owned but constantly turning away punters so hardly need the exposure.) In their case, WGT has more to gain from the relationship than they do.
But the resort courses could use WGT as splendid marketing. A captive audience who would love to pay good money to play those courses in real life.
As long as WGT continues to add the championship courses, more resort courses like Bandon (+ Pinehurst, Kiawah and Pebble Beach in fact, which are also resort courses) are absolutely welcome and they should pay for the exposure or at least share the cost.
Hint: Wolf Creek, Harbour Town, etc.