http://www.usflag.org/us.code36.html#176
§176. Respect for flag
No disrespect should be shown to the flag of the United States of America; the flag should not be dipped to any person or thing. Regimental colors, State flags, and organization or institutional flags are to be dipped as a mark of honor.
(i) The flag should never be used for advertising purposes in any manner whatsoever. It should not be embroidered on such articles as cushions or handkerchiefs and the like, printed or otherwise impressed on paper napkins or boxes or anything that is designed for temporary use and discard. Advertising signs should not be fastened to a staff or halyard from which the flag is flown.
hmm… I have a few car lots around here that should read this.
for respect, maybe a trip to http://www.ushistory.org/betsy/flagetiq.html is in order.