You have my sympathy but always wondered, do you get many people actually buying or do they just come in, browse and go away again?
I'd imagine the latter are quite annoying for you?
I think the 'sales' people are used to it. If you go into any store mid-morning, there is more staff than potential customer. I do, however, feel sorry for the staff who must stand there for hours on end with a smile plastered on their face just in case.