It's easy to get rid of. Open up a chat session with PKR and ask for the button to be removed. After the usual security questions they remove the Blackjack button from your client.
I asked for it to be removed because I clicked it a couple of times by accident when checking the lobby. The first time I didn't know what the hell was going on because I hadn't seen the button and thought I was getting the lobby menu up.
I have no interest in playing Blackjack so I was happy when I heard they would remove the button
I agree with the moans ... they have a Casino client so why not leave it there?