Here’s the secret. Tell the guy at the gate you are there to meet “Mark” (or anybody) from collections and they’ll just let you park free. Show a military ID (even retired) and that helps with the illusion.
Can't say I've tried this, but it reminded me of one time at the Atlanta Aquarium, as I was waiting in line, a HUUUUUUUUUUUUUUUUUUUUUGE (literally thousands of kids) collection of school groups were cutting us (the reason I can't remember). I took Joe Gatto's approach and just started yelling "Larry! Larry!!! Larry, wait for me - I'll be right up! Larry!" No one, not a single teacher, worker, or anyone said anything, and we made it right to the front to present our tickets for entry.
I do not think I know a single Larry.