Go with the flow, but make sure that your company allows enough time for you and your crew to do battle with these knobheads. Personally I can't stand the scum who "do security" at airports and I will neither speak nor help them in any way whatsoever. Also, to do battle with them on their own terms is doomed to failure. Instead, fight them on their your terms. If the aircraft is blocking a stand, so be it. If this results in a late departure, tell your company (and the pax) the reasons why. Especially is you are being charged parking by the airport. I'll not be rushed into moving before we are ready and if that is inconvenient to the airport, then so be it. Also, remember, you mustn't let these people on your plane - for security reasons, obviously! It's nice denying them access.
PM