Not really the same thing......
Che t-shirts are worn by retarded suburbanite college kids who want to be seen as revolutionary and anti-establishment, and are honestly too ignorant to actually research the face they are identifying themselves with.
In effect as popular definition of the image of che leans more and more towards simply seeing it as a sign of revolution, much like the upraised fist, the peace symbol or even the thumbs up..
The Stars and Bars however are worn by people fully aware of its place as a symbol of institutionalized opression disguised as "southern pride". Popular opinion defines it as a symbol of hatred.
Regardless of an image or symbols true meaning, or anythings true meaning for that matter, the actual definition of something is unfortunately set by public opinion.
Take for example the Swastika, an ancient symbol with multiple origins as diverse as ancient egypt, asia, and nordic cultures. A benevalent symbol, often associated with fertility, fortune, and other good tidings, forever changed into a symbol of hate, prejudice, and genocide due to it's relation with the Nazi's. Or the ever popular thumbs up, a sign of good tidings, but originally it was the sign used by roman emporers to signal execution, thumbs down was for mercy. As mentioned previously, before christianities embracing of the cross, it was a method of slow torturous execution, not a divine benevolent icon.
The literal definition of faggot is a bundle of kindling, gay used to mean happy, queer just meant strange, and yet due to popular definition, these words have all unfortunately been used to demonize homosexuality.
Regardless of origins, regardless of literal definition, popular opinion is what defines symbols and icons.
So by that token, afficianados of the stars and bars, a symbol they know full well is associated with racism and bigotry, as well as treason, are more offensive than afficianadoes of Che t-shirts/posters, who almost never have any clue of the man they are associating themselves with. But, Che fans are usually far more ignorant than CF fans, so it all evens out.
Anti-Organized Religion, Pro-Choice, Pro-Gun Rights with limits, Pro-Legalization of Drugs-Prostitution-Assisted Suicide, Pro-Gay Marriage,