The Hockey player Happy mentions in the beginning of the film is Terry O'Reilly. Once during a game he jumped into the stands at Madison Square Garden and fought with a fan.
The concept was inspired by Adam Sandler's childhood friend Kyle who was a hockey player. Kyle regularly played golf with Sandler and Sandler's father. Kyle is now a teacher in Manchester, New Hampshire (Sandler's home town) and coaches the high school hockey team.
When Happy is in the batting cages, Chubbs pulls the plug for the pitching machine causing it to stop. The cable is visibly unplugged in the next scene but when the young boy enters the cage the machine still works.
During the final round of the Tour Championship, Shooter is forced to hit the ball off of Mr. Larson's foot. Even if a spectator let a ball come to rest on their foot, PGA rules would clearly give Shooter a free drop.