Some people collect dice. They come in a wide variety of colors, including resin blends and different metals with a variety of fonts and designs, and sizes. I have boxes of dice. It's relatively normal for a player to have a bit of fun by matching dice sets to a character or campaign. The other thing I would point out is that someone rolling for addresses wouldn't need a giant bag of dice. Even if you are rolling for 20 different variables, you can do that with a pocketful of dice. They guy in the hobby shop was just as likely to be a collector. They can be expensive, but plenty of people splurge on hobbies or get carried away collecting all kinds of things.

Having said that, I get being worried for ones child, and the sense that the killer can choose anyone arbitrarily now does limit the feeling that you can strategise.

As far as suite A or B, all the killer would have to do is roll a d2 and have 1 stand for A and 2 stand for B.