Is "Buy Blue" Unamerican or Just Stupid?

Buy Blue is a wacky concept that essentially encourages leftists to boycott companies which made major contributions to the GOP and to buy from companies that contribute to the Dems. It strikes me as almost anti-American. I mean, I could see if it was the American Communist Party or the Nazi Party, but do these lefties see us Republicans as so offensive that they shouldn't even buy a burger from a company which supports the GOP (I know, a lot of libs wouldn't eat a burger anyway - "meat is murder" and all that insane PETA drivel).