It is a love hate relationship for me. I hate their liberal angle, but I love the level and depth of their reporting. When they get to beg for money "membership supported radio, you know!) I turn them off, and listen to CDs instead.
Call them up. Tell them that you aren't giving another dime but that you want the free CD, coffee cup, or Nina Totebag. When they ask you for a donation tell them you already gave at the tax office.