I'm not a member, but have an idea for you. I think if you want to expand intrest into your club i think you have to expand its boundries. What i mean, is to advertise and promote other areas of casino collecting such as, dice, slot cards, casino playing cards, swizzle stick, casino art, lighters, matches, ashtrays, books anything with a casino logo on it. Then i know you would have a bigger turn out. You might say this is casino chip and gaming token collectors club, which i know but its an idea. Also from what i hear is that you do have those other i mentioned above but only advertise about chips, which some people might not be interested in. I know alot of people that are interested in other area. I'm not saying don't promote your chip collections or hobbies, yeah you should do that, but try and get the other kind of hobbies in there too.
Also, maybe the week or two before the convention someone that lives in the vegas area could hand out papers down on the strip somewhere to promote it. If people can hand out adult entertainment cards, i think you could hand out something like this, post them on telephone or light poles too, plenty of way to get free advertising out there. Just think people are going to see them or hear about it, that person you gave a paper to the week before the convention might not be around but maybe he takes that home and tells all of his/her friends about it and then some of them become very interested in it. Just an idea