A couple things...
The conference in RI was on the smaller side (as it was also their first conference). Knowing a little of what it takes to set up these things, it would've been a lot more expensive for a local hobbyist to set up a booth at a conference like this ($300-$500 +) versus a storefront or vendor.
The FFM has PLENTY of local hobbyists there, so you need not worry. When Jon says "big names," he's speaking of Dr. Mac, Jason Fox, etc WHICH is a HUGE draw for the hundreds of people who come from all over New England for this event. Having all the other "local" hobbyists from CT, MA, RI, NH, NY, NJ, MD is an added bonus.
Last year was our first event, and we had plenty to choose from. What we heard last year (as we got there early and helped set up) was that they added space for additional vendors.....which I heard they are adding even more space this year.
You will not be disappointed.