If a good player misses a low percentage shot, they are playing the poor lie after the fact. It should be absolutely part of the game, as it is with snooker. Or, moreover, when there isn't a clear shot for a break out, then an intentional 'negative play' or snooker should be expected and executed, then appreciated by the opponent. It takes skill to run a table; as it does to leave a bad lie. Bad luck should never really enter into the game, or the attitude of a competitive play.
On the other hand, where there is an outlier and an obvious 'dumb luck' shot, it is proper to raise one's hand to show it was unintentional. Especially when a ball drops from an unseen plant, and play continues. It's good form to show appreciation both ways.
Bad feelings have no place, unless there is poor sportsmanship in play. Nobody likes a braggart.