Yes, it sucks.
However, you were buying a service which goes directly against Blizzards terms and conditions.
The response you got from blizzard is basically a default they give to people (be it gold farming/purchasing, powerleveling, or just trading a lot of gold in a weird manner).
So this isn't really a complaint, you took a risk and got caught, bummer yes.. but don't use a main account to powerlevel.
If you really want to do it and get a nice 70 leveled up with no effort.. buy an account, get it running, make a level 1 whatever/whatever you want it to be, pay them for 1-70, check daily.. shouldn't be a problem.