There's nothing in the rules that says you're not allowed to use temporary mail sites. I also hugely doubt that any temporary email site is the reason for your deletions. In reality, they might use it as a first-stage detection mechanism, so anyone using guerrilla mail, supermail, extramail, etc will be observed to see if they are botting, but they cannot and would not delete you only for using a certain email domain.
Personally, I have a set of domains of my own which I use. I even have a Linux box set up at home which hosts all my mail servers. I'll soon be transitioning to run my main mailing accounts from it. It's much safer that way, since if they do use email domain as a "first sign" of botting, they are unlikely to add a custom domain to that list.