No, they aren't. Premium/Pro accounts are never deleted, even when inactive.
Originally Posted by SpaZzn
Which means that first your subscription expired, then some time passed, then you were sent a reminder mail ("your account is about to expire, please login within two weeks to keep it" or something), then you've ignored that mail (it only needed you to log in, doesn't require playing games to confirm activity) and only then it was finally deleted.
02:23.18 <sponge> if you have a sub, a clan founded, or a trophy case award, it'll never delete
It's a good system designed not to harm anyone. No reason to be mad about it.