This recent search and seizure:

http://www.p3air.com/2011/any-takers-pilot-and-his-compamions-decline-570000/

certainly points to the motivation for tackling tips.  The rewards are split between the various forces.  My own story is somewhat similar.  Landing in Calgary one night we were met with 3 customs officers and a customs beagle.   My wife and I consented to the search of the aircraft and a pastrami sandwich was seized.  We had brought our lunch from Florida for the day-long flight.    I watched as an officer thumbed through the sandwich while conferring with Ottawa by cellphone regarding the disposition of the contraband.   Eventually it was handed back to me, presumably for me to consume, because "anything less than 4 ounces of meat" was not a concern.   This was in the day of mad cow.  I asked if the dog wanted the sandwich and I was told that he wasn't "an AG dog, he was a drug dog".    Then I was asked why we always arrive in Calgary at shift change time indicating they believed this to be a suspicious pattern.  I felt silently proud that they thought me to be smart enough to figure that out.   I explained that if you leave Florida late in the morning and stop at a few places then you end up arriving in Calgary at the time we arrived.  We now try to avoid arriving at that time.

Paul
Daytona