Personally, I prefer that people assume I know nothing. Explain it to me like you are talking to a 3rd grader. Let me be the one to establish my that the bar on my knowledge of the subject matter is higher than that, then we can go from there.<quoted text>
Probably not, but still as a customer, the sales people might want to assume that I know stuff, have money, want to buy stuff, and treat me accordingly. Even if I don't know stuff, they should do their job and treat me as a customer who wants to buy stuff from their establishment thus ensuring their continued employment.
In my own job, working with people in different departments to create computer programs to help them with some aspect of their job, its annoying as hell when people just assume you know all the ins and outs of their daily duties. Start with the assumption that I will have no idea what you are talking about and build from there.