i don't get rude, but since i didn't ask them to call and they somehow got around the do not call list, when a telemarketer calls - no matter who it is, i ask them politely to hold on. then i put the phone down.
a few minutes later it does that fast beeping , "off the hook" thing, so i hang up.
they rarely call back.
being paranoid, i wouldn't doubt that there's a "don't call - waste of time" list that telemarketers keep, or maybe a sucker list. people who talk with anyone.
A true lover of nature does not despair now that his mistress has turned a colder cheek.