It is more cost effective to produce coins as opposed to printing bills, so the government has made efforts to make the dollar coin catch on in popularity. It has reduced its size to reduce weight and bulkiness, but the public still prefers the dollar bill.

Why? Well, I spend nearly equal times in Canada, Mexico and the U.S. every year. In Mexico the 10 peso coin has replaced the 10 peso bill, and Canada of course has its $1 and $2 coin with its lowest denominated bill being $5. I find them impractical, too many coins in my opinion. That is probably why Americans esteem their dollar bill so much; yes, it may be costlier for the US Treasury to produce, but in terms of convenience there's nothing like it. Also, you have the image of the U.S's first President, perhaps the only one which can be esteemed and venerated by all people of all political persuasions in the U.S. It seems, from a popular standpoint, rather obscene to even suggest retiring old George from circulation.

Eventually, if the actual purchase value of the US dollar were to drop, that will most likely bring about the phasing out of the dollar bill. When that does happen, it will be sad for a multitude of reasons.