The grandparents and grandchild with a dog in the scene where Simms yells at them after asking for an autograph are played by Kevin Costner's parents, Sharon Costner and Bill Costner. The grandchild is played by his son, Joe Costner.
Kevin Costner is shown at times drinking Shiner Bock Beer. This beer is brewed in Shiner, Texas, and not well-known nationwide. Where has this beer been in movies before? In Fandango (1985), in the hands of Kevin Costner.
According to the US Golf Association, a player can borrow a ball from another player as long as it's the same brand and model, so if Roy hit his last ball into the water, he may or may not have been disqualified, as Romeo stated.
In the bar after the first round, Roy commented that he didn't shoot an 82 because he missed a four footer on the 18th. The scoreboard showed that Roy shot 5 (par) on the 18th to shoot 83. Yet, following Roy's shot into the water on the 18th in the third round, broadcaster Jim Nantz stated that he had found the water for the third straight day. If Roy had put the ball in the water with his second shot on the 18th in the first round and missed a four footer on that green the best score he could have had would have been a 6. (Drive + shot into water + penalty stroke + approach shot + missed putt + made putt = 6)