I do believe they are preloaded in a sense. I use mine in my own room, therefore it has nothing to do with where you walk. I have also won sitting down, which was a total accident. I actually thought I wasted the pin until I got 2000 credits for it.
The win is in the pin, not where you are standing. Have you ever used like 8 or so of them in a row? I did on one of my characters right after opening one morning. I got 2000 credits, nothing, tiki, nothing, sorcerer, nothing, 5000 credits, nothing. I think they are on a rotation. Like the server passes out gifts in an order..one for you, one for you, one for you, none for you, etc.