While saving the casino password on the browser maybe risky as someone (probably any family member) can access your computer and then access your account. In some cases, the password may be comprised / hacked, being saved online in the browser but it really depends on how much fund you keep in the gambling site.
For example, I do not keep much funds in the casino wallet and hence i prefer to save my login details in browser. I get the advantage that i don't have to manually type the password each time I login and it saves me time. At back of my mind, i know I don't put too much amount in the gambling site and till now, I haven't faced any bad situation

I understand your stance, but perhaps you'd be interested to password managers as mentioned by notocactus? You still get the convenience of not typing manually and don't have to remember the particular website's password from a-to-z, while getting optimal security because many reputed ones are open source and provides better encryption of your data especially locally. It can make encrypted backups too.