My point is that the businesses there are doing what, in their experience, is best for them. They've all heard the "Fast nickels is better than slow dimes," adage, but they have to come in twice as fast.
Now, when I"ve had a table, it was more of a yard sale, than a "real" vendor. In fact, one year I had the Mass DOR ask for my tax ID. I told him that I was there as my table's contents were not going to go over on the front lawn, in the PRM. DOR guy agreed and went away.
So...dealer has to rent tables (IIRC $75 per table), probably pay for power and Internet, and pay for the employees' time, as well as their own. Plus the travel time, set up and break-down.
I'm not pleading poormouth for the dealers, but a business will do their best to make a buck. If selling cheap was the way to go, they would, I'd guess.
As for building business, if they're local, I'll go there, anyways. If they're from East Treestump, I'll see them at the show. With the exception of some specialty items, it's all just a commodity. In fact, I needed some High Standard parts. I could have gone to the show, and asked the Schlitz Hat guy, and wandered around, and maybe found what I needed, or not. Or, gone online and ordered what I needed. Internet won.