Code Red no, but sure as heck not code white.
If I saw someone standing outside a vehicle at an atm I would stay way back from them. I normally don't pull right up behind another vehicle at an atm anyways. Common courtesy, do unto others/golden rule. I don't want someone starring ovef my shoulder as I enter my pin, and I don't do it to others.
That being said I would have the person on foot in my radar, if they do not get into the vehicle at the atm and leave with them then I am not pulling up to the atm.
I think tat since several other peopel complained to the tellers at the bank about these two guys I would ask to talk to the manager, explain that not only is it a safety issue if these guys step into oncoming traffic at the atm lane, it most definitley IS a security issue. If the manager refuses to agree to talk to the tellers and have them call 911 next time it happens then I would make sure to tell the manager I will be transfering my accounts to another bank.