The buy and sell "crafters" are very hard to compete with. The only thing that can save you are educated buyers that are looking for quality. Quality is something the 1-800-Restock crafters don't have in most cases.
Don't know what type of shows you do but if you do mall shows I would look into dealing directly with the mall. For about the last 5 years, before retirement, we rented space directly from the mall and didn't have to deal with craft show promoters. Usually about the only advertiseing the promoters do is the sign outside the mall that nobody reads. Then on setup night you find the promoter has assigned you a space in the broom closet and let 50 buy and sell ":crafters" into their juried show.
When you deal directly with malls you usually get more space, a better location,and usually don't have to compete with buy & sellers. We found it was more expensieve and liability insurance was required but sales were also much higher.
I would also recommend keeping a list of past customers in each area and sending them time and place when you're going to be in that area again.
Marv