Stupidity: When the Hilts discover they're 20' short of the trees, why wouldn't he "dirty up" his white/light tan pants so the tower lights wouldn't expose him so easily?
Suggested correction: Because he would look scruffy and dirty once he got out. He was the Cooler King and knew his way around after all.
I would suggest in the reality of the escape, light colored clothing would not have been worn so as to blend in to the night and the surrounding environment better. The light slacks were strictly for artistic reasons.
Stupidity: There is no logical reason for a bookkeeper to be present at the liquor deal on the Canadian border and even less of a reason for him to bring the primary ledger with him. This is compounded by the fact this is merely a secondary bookkeeper and the main bookkeeper is subsequently subpoenaed by the district attorney.
Stupidity: Outside the bank, Mike and the first merc are having a shoot out across the parking lot. There is lots of room between them and around them. Yet a random construction worker, with a clear view of this shoot out happening, suddenly decides to take off running into the line of fire between the cops and the robbers and gets shot in the leg. Their was no reason for him to suddenly decide to run between them shooting at each other into the line of fire. (00:44:35)