I have to say that I had a similar experience there recently. When I gave the same generous tip that I have given the past few times, it was" looked at" as if it was not enough anymore! No words were spoken, but the look said it all. I was a bit put off.....
I stopped going to Hey Man because there was a guy who in the middle of my massage requested a tip amount, so I was not relaxed at all during the session... I have no problem tipping well, but I do have a big problem being asked for, or told about a tip before, during or even after my session if I myself have not asked for anything extra yet.