The thing with the regulations of the United Kingdom when comes to cryptocurrency exchanges and other services which try to facilitate Bitcoin/alt coin speculation to a wide percentage of the population of the country is how strict they are when comes to allowing or not people to take risks with their own capital. I have seen people from the UK who literally need to take a quiz before being able to trade and also go full Know-your-client, not basic level but full level (physical address included). It is so strict that actually it would be silly for casinos to adopt those same relations when comes to betting markets, as if people did not know they are actually risking their money.
Also, we must keep in mind the regulation of the United Kingdom is not international/global, so if a casino was forced (for some reason) to comply with those warnings, quiz and also full KYC before allowing their gamblers to bet, then it would mean that casino would fall into disadvantage in comparison to others which do not make the process of betting a hassle, which make it as simple as depositing and choosing where to bet.
I am okey with people getting more educated about the world of gambling and betting, but building barrier after barrier, after barrier in order for someone over 18 years old to place a simple bet sounds rather like an exaggeration, if you asked me.