End users at large enterprise companies have zero say in the support browsers of that organization. These policies are put in place by their IT organization which in some cases manages all applications and patches that are pushed down to an individual's machines. In those large companies even Windows patches are managed in house and not through the standard Windows update process. I think those companies will easily stomach an additional charge for IE6 since they're used to paying for everything else. That said, I'm sure they'll use their size to attempt to negotiate themselves a better price.