Tipping is one of the social graces, and as such, it has an upper bound as well as a lower. In other words, it's possible to tip too much, in the same way that it's possible to hold a door open for someone too long. Politeness overdone wraps around again into rudeness.
I know, it's odd. And I'm not saying your beneficiary wasn't thrilled and happier. I'm just saying, you know?
Cross-posted from another thread