Below is a graphic that illustrates the proportion of team golf titles held by the host team. Just over 64% of the titles were held by teams that won them at home. McGinley's claim is supported by the data. The tournaments included in the calculation are: the Senior and Junior Ryder Cups; the Senior and Junior Solheim Cups; the Presidents' Cup; the Arnold Palmer Cup; the Curtis Cup; Walker Cup; and the Men's World Cup of Golf. The inclusion of the last of these tournaments is questionable as there are more than two teams competing and, therefore, a home win is less likely. As many of the tournaments are held only every second year, the calculation is based on the current holder of the tournament.
There is some evidence to show that when it comes to refereeing decisions, there can be a bias towards the home team. Some evidence. However, there is also evidence to the contrary. The Butler brother of this parish have found little evidence of home bias in the decisions about added-time (here). Hlasny & Kolaric struggled to find evidence of home bias in disciplinary matters in a recent Journal of Sports Economics paper (access their paper here or my review of it here).
My disposition is probably to accept that there is possibly some home bias in refereeing decisions. I'm not sure if it is a product of my economics training, my sporting experience, or my personality. However, the home advantage that teams have in golf makes me wonder.