Would really be just dumb if any business nowadays wont really be considering or including social media promotions yet we know on how big the traffic is within this place even
though its not really that crypto based or related traffic but it would be sensible if this would be included on the list yet potential users or gamblers could really be hooked up.
As long your budget or marketing allocation do fits you then all possible mediums should really be included in terms of exposure/promotion.
I'm sure every gambling platform will campaign its platform everywhere on every social media that is filled with global traffic, whether in paid advertising or actively engaging in a pool of gamblers groups. So although not really tied to crypto users but if the offer is very attractive it will bring in a lot of users from active gamblers on their platform.
You should know that casinos or any gambling related websites or blogs that provodes betting tips is not accepted by major advertising platforms. This is why they pay a lot in exposures in forums like bitcointalk.
This forum is one of the best place to advertise which if Theymos has new adspace auction, some of the marketing staff bids o it. Advertising in gambling forums will work as along as there is traffic.