Re: Simple social engineering would break both the door and the safe
A confident manner is all you need. 2 stories from my last company illustrate:
1. Someone walked into one of the branches. Overalls and clipboard. "Sign here please". Put £10,000 of copiers onto dolly, and wheeled them out to his van. Byeee. Wonder how much he got for them down the pub?
2. Chap walks into head office. Finds a nice side office with 3 people in. "I've lost my contact lens, can you help me find it?" Gets them all into the gents looking, then he remembers it might have fallen out in the car. Pops out, nicks their wallets, then to allay suspicion pops back into the gents, "Sorry chaps, it was in the car, thanks for all your help." Leaves. The credit card company spotted the odd transaction, and phoned one of the guys to check it, which was the first time they noticed.
As you say, I've never had trouble getting into a hotel room. At one family occasion my brother managed to go to the desk and get a duplicate key to someone else's room. Even though we'd all booked and paid separately. And the one time I've had to ask to be let back into my room, no questions were asked but the number.