I know what you mean Paul, I wasn't really talking about "official tipping". (Or as I call it on the expenses account 'custom fees'.) I was talking about having to 'pre-tip' to have chocks placed under the wheels.
NZLear, don't get me started on KTEB. I finally decided that we would go back to back to Atlantic Aviation just because of what you are talking about, even though other places had cheaper fuel prices.
Now, in the US I tip for the following services (I should have stated this at the start of this thread.)
Passenger baggage handling from the airplane to the Limo.
To competent line service personnel to put the covers on the engines and other bits that need covering.
Lav servicing, especially on the Falcon 50. (Nasty job.)
To the Van drivers.
And of course for any above the call of duty services. Such as getting flowers for the boss's brand new fiancé at the last minute or going to a local store to get some strange item at the last minute. Any corporate pilot that has been in this business for any time at all knows exactly what I mean.
I have always made sure that all the employees of our home base and the very popular ski resort (Okay, its Aspen) that we operate in and out of on a regular basis are given yearly bonuses.
It pays off in the long run, that was I was referring to about be placed ahead a few spots waiting for fuel.