I agree with you that CoinMarketCap never advertises gambling. It is usually handled for use in the use of cryptocurrencies Casino sites are different in the crypto market Making money here is much easier. Gains more exposure on social media.
I see some ad banners of some casinos on coinmarketcap.com, Sportsbet.io, Bitcasino.io. They are casinos I saw last few days. Maybe more sites are advertised and displayed on coinmarketcap.com. I don't know there will be changes in advertisement strategies and requirements on coinmarketcap.com because of impacts from Binance.
I still can't believe that binance bought out coinmarketcap, but looking at the website they didn't really bought it to integrate with binance and somehow make it like their website or anything. It looks like they bought it because they think it could be a business all by itself. I wouldn't really spend that much money on a ranking website if I wanted to grow, but it has a ton of users so I guess it makes sense to them financially.
About the ads, they would definitely allow gambling ads, I have seen plenty of gambling ads there, and I think binance doesn't mind as long as its a legal situation, if you are running an illegal casino with no license you wouldn't go too far, but if you are doing something legal and not nsfw, you can advertise anything there, including freebitco.in which would profit anyone highly.
The website is important because its one of the metric measures that determines the state of the entire crypto market. Are there really any other alternatives out there? Not really pretty much everyone uses coinmarketcap. You need to understand that whichever altcoin they decide to track, it determines the total crypto market cap and total bitcoin dominance hence its important that the service is out there.
I didn't know they don't allow crypto gambling ads. Most of the ads I see on there are ICOs and Trading exchanges for crypto or forex. And honestly I don't see how casinos are that much more riskier when they are still listing speculative investment assets anyways. Maybe there is another reason they don't list gambling sites. I think it might have to do with regulation in certain jurisdictions. Which is too bad because besides Bitcointalk forum and coinmarketcap there really isn't any better place out there to advertise your affiliate site.