I can't imagine that she would do something illegal or shifty on camera, just in the hopes that no one would happen to review it. Would she know whether or not management looked at the tapes all the time, or just when something seemed strange? I know I would assume that if there is a camera, I am being watched, JMO.
I would assume I'm being watched as well if there is a camera. That being said, if I am doing something illegal or shifty I would be well aware of the camera angle and know what area's are covered. Lets say I was going to deal drugs out of a drive thru coffee shop. And in no way shape or form am I suggesting this is what Sam was doing. But, I would be very aware of camera angles, when the boss called, when money was deposited, when the trash got picked up, when the deliveries were made, what customers were regular and when they got coffee on and on so as not to slip up.
Do I believe drugs are involved in her going missing? I have no doubt in my mind. But that's just my opinion.
Do I believe she got in too deep and had minimal intentions and didn't realize how serious things were? yep, but again that's my opinion.
I have more opinions but thats it for now.
I truly hope she is found and found safe and at this point I still believe she is alive and being held.