Courses around me apparently had a big problem with people picking up balls and taking them because all of them around me have always been ridiculously strict about picking up balls. There were a couple holes that went along the back of the driving range so those holes would occasionally have balls around. Whenever we would get there we would just pick up a few and it would pretty much take care of any balls we lost that day. Then they started putting up signs, then they started stationing a worker around that area the entire time. Seems kind of crazy for just a few balls, unless people were going by there and picking up a ton.
Ah that sucks. I suppose if they're range balls, they want to keep them for their stockpile, but range balls were always kinda shitty anyway so I assumed they were cheap to replace.
Finding lost balls always seemed like part of the fun. At the very least it helped make you feel better about looking for your ball in a ditch when you came back with 4 or 5 more. When one of our friends got an extendable ball retriever thing, the ponds and muddy ditches were like a gold mine for balls no one wanted to retrieve.
This is making me want to go play some golf.
Edit: It was always good to find the golf ball standards like a Titleist or Dunlop ddh to add to your collection, but every now and then you'd find a rare Nike ball (dunno if they'd be as rare now) someone spent too much money on, or a ball with some crazy custom print on it.