can't see the trees
I'm with @a_yank_lurker on the possibility that emails could be deleted because they get confused with a lot of similar span. I'm a nobody, but I get an awful lot of emails to renew my domains and they're almost all scams - not to mention the snail mail scam renewal requests I get. In a large company, how likely is it that these emails end up in the account of somebody who is less skilled and overwhelmed with registration spam?