The more I think about, the more I think, what an excellent idea. Prpixel, the point you make about you needing to sell listening space for 8 hours a day for 3 years, to break even, seems to miss the point. I presume we are talking of dealers opening up there top listening rooms to the poor unwashed. They do'nt have to cover the cost with selling listening time as you are selling the kit too.
I personally wo'nt go to a dealer unless I am in the market to buy, it is'nt fair on them. It does'nt mean I am going to buy, just I might if I am impressed. Yes a live gig might be better, but only one artist and not playing what you specifically want to hear.
So the more I think about it, the more intersting an idea it becomes. Dealers do this already with open evenings to listen to a particular set up. Why not offer listening sessions when they are quiet. They build a relationship with potential clientele and you get a guilt free audition. Everybody seems to win here.