So far, 32Red is the only one in the list above that uses non-overwritable cookies. I know there are more, but I haven’t discovered them yet.
@Dominique 168788 wrote:
My favorites would use overwriteable cookies as well as sessions
Same here. 
Goldfinger wrote:
You can add Bet365 and Ladbrokes to the list.To the cookie list? Did you happen to check if the cookies were overwritable?