A Doctor, Social Worker and an Engineer arrive at their golf club early one morning for a quick round. But in front of them on the first tee are three people who appear to be blind, and the greenkeeper is doing his best to help them.
After quite a long wait, these three eventually manage to tee off, and are heading off approximately towards where their balls went. So our three quietly ask the greenkeeper what's going on. "Oh, don't you remember the bad accident when the clubhouse was rebuilt? These three were working on it at the time, and had their eyes badly damaged in the flying debris – they're virtually blind. Since then we've let them play here free."
The Doctor is horrified. He says "I must get them into my surgery at once and see if there's anything at all I can do for them."
The Social Worker is equally concerned. He says "I must check up on their disability benefits, and make sure that they're getting everything they're entitled to."
The Engineer isn't quite so impressed. He just says "Why can't they play at night?"