I stood in the Exec. class line and watched 10-15 pax in the economy line get checked in. Meanwhile the Exec. class line did not move at all, very frustrating. We ended up leaving the line and joined the economy line and got checked in much faster.

Is it a big deal? No, of course not. Airports are full of waiting. Waiting to check-in, Waiting in a line to get pointed to a Security belt, Waiting at the security belt for everyone to take shoes off, etc, wait at the MLL to give you BP to the agent, Wait at the gate for them to call Priority Boarding, Wait in a line with all the Priority Boarding people, Wait in the jetway for the congestion of customers to show their BP to the Flight Attendnat, Wait in the aisle for the person to stuff their large carry-on in the overhead bin.
My point? If you go to an airport and expect not to wait then you need a reality check. Only start complaining if something big happens like you miss your flight because of the slowness of the AC rep, or you get downgraded, etc. Save your complaining for something worthwhile.