I am often in the YVR transborder 'FastTrack' line behind families with strollers, passengers in wheelchairs, and then pushed aside to let flight crew pass.

On a positive note, on more than one occassion I have seen a CATSA agent turn on her supervisor and insist that the FastTrack line be kept for its intended purpose, ie flight crew and frequent flyers/Nexus holders.

MCO used to have a 'family line' - I would suggest that YVR invest in such a thing during busy periods, as I would think that the families don't like feeling pressured to 'hurry up', whether verbalized or not.