it's pretty obvious he didn't have a plan, meaning this theft wasn't premeditated... he just took two bottles and the idea of not paying for them hit his brain faster than his face hit the floor
While I appreciate the attempt at a joke, it looks like he planned to steal, judging from his shiftiness, but he just didn't do a very good job with the planning.
to me it looks like 0 planning and that he just took the bottles and the thought "I could just take these" popped into his head. He seemed to casual, since there was nobody at the counter to stop him, something he possibly noticed just then triggering this whole event
As you said, it is just a joke, though. That's how it looked to me but of course I could be wrong. Maybe definitely wrong because I'm giving the guy too much credit to have had some familiarity with how those doors worked and only a sudden, and poorly, if at all, thought out, impulse would justify... but I might be giving him too much credit, I'm probably wrong, but it's a joke so I thought there's no big risk sharing it.