A pearler of a conversation

Alright, so my Oystercard blue plastic wallet was getting a bit worn and falling apart. So much so, in fact, that once or twice the card itself had fallen out of the wallet into my pocket.

Therefore the next time I was passing through a tube station (which happened to be Temple), I went to the old guy at the window and had the following exchange with him:

Me: "Have you got any of those plastic Oystercard wallets?"
Him: "What's the magic word?"
Me: "Please?"
Him: [gets new wallet and pushes it under the glass, plus he may have said something like "That's better" but in honesty I cannot recall]
Me: "Thanks" [walks off]

I spent the remainder of the short walk to my office thinking about the exchange, and whether my opening question had been impolite. I have concluded that since I didn't actually know whether or not the guy had any wallets behind the desk, my question was a genuine 'fact-finder' and therefore didn't need to be adorned with P's or Q's. The guy probably thought I was directly asking for one (that would have been my next question) and therefore demanded politeness.

Does anyone concur or disagree with my analysis? If it is correct, I wonder what someone with (say) Asperger's Syndrome would do when asked for the magic word? Surely someone with such a strict literal interpretation of the world and language would be bemused, since they would not be able to make the link that the guy was inferring that they were asking for a wallet?!

I'll stop there.