Coinbase has made it clear that it frowns on gambling and I thought everyone knew that. But then I really do not see anything wrong if coinbase wants its customers to be more careful with how they spend.
Today it is gambling, tomorrow it is porn... the day after that it is beer... where will it stop? You should use your money the way you want to use it, not the way someone else wants you to use it. I
have seen some statistics being shown, where Coinbase even shown how much junk food people bought with their coins. I see no need for them to know these things, no matter what their reasons are.
Do not let these companies dictate to you, how you can and cannot spend your money. Use Bitcoin directly, wherever possible..