Here's where we were completely stymied by a well-placed plainclothes security guard. We almost had him bullshitted, saying that we were there to do an official promotion, but he called up the chain of command until finally a higher up came out and asked us to "please wait on the other side of that silver line in the ground... this is private property." Then they retreated to behind the glass doors and watched us. After 15 or 20 minutes, we realized they weren't coming back out. Very smooth.
We did our spoof ritual outside, but somehow it wasn't the same.