It seems like the real problem here is the administrative process... the OP makes it sound like a unilateral decision with no recourse... and maybe less extreme measures could have been taken, such as letting them know what aspect of their business was high risk and giving them a chance to spin it off instead of just booting them. It is incredibly inconvenient to have to switch payment processors unexpectedly, and having a reputation for booting customers unilaterally will not benefit your company.