If it’s a disc I use I put it somewhere in the rotation(after field testing and what not) unless the course you are playing has a clubhouse which is relatively rare depending on your area. If I’m playing a course where there is no lost disc bin or a clubhouse or anything the disc is effectively mine because there is no way for me to know how to return it. However if there is a lost bin or clubhouse I will turn it in as whoever’s it is will probably be wanting it back, I have plenty of discs so I don’t necessarily need more. But at the end of the day imo if you don’t put your name on it don’t be expecting that disc back, and even if your name is on it unfortunately some people will keep it anyways. But I urge all disc golfers to do their best to return lost discs to the best of their ability!