One of these days I think it'd be fun to see a booth at a show where the manufacturer doesn't even bring their own stuff. It'll be "nah, we're so confident in our gear we don't even need to bring it, so instead here's a whole bunch of cool vintage stuff that we audio geeks have collected over the years".
Hmm, probably that'd be fine with a speaker-only manufacturer using old amps, or vice versa. Maybe not so much when you build both.
I could kinda see it being a draw too. Nostalgia is a powerful thing, and getting more traffic to the booth is still more eyes that will see your product even if the initial draw was something else.
But hey I'm just an engineer, not a marketing witch doctor =P