heh! That's one way to do it. Here's how to stop marketing phonecalls permanently:
(copied from http://www.obviously.com/junkmail/ )
Federal law prohibits telemarketers from "Initiating an outbound telephone call to a person when that person previously has stated that he or she does not wish to receive an outbound telephone call made by or on behalf of the seller whose goods or services are being offered.". You may simply interrupt the telemarketer and say "Please permanently remove me from your calling list". Remember that they just interrupted you. If the same people call back, they are violating the law. Ask them for their company name, supervisor name and phone number. If you wish to quote Federal law to the telemarketer, you may read it at Federal Trade Commission: Telemarketing Sales Rule - http://www.ftc.gov/bcp/conline/pubs/buspubs/tsrcomp.htm
You can register at the National Do Not Call Registry: https://www.donotcall.gov
Most telemarketers should not call your number once it has been on the registry for 31 days. If they do, you can file a complaint at the Do Not Call website. You can register your home or mobile phone for free. Your registration will be effective for five years.
The problem is it doesn't stop non-profit organizations, and there are a 4377 of a lot of them out there.