Do you hate the $1 coin?
First of all, WTF penny? Go away. 
I am 100% in favor of getting rid of the penny. Heck, we could probably get rid of everything south of the quarter, and I’d be happy.
Ok, so the main reasons people keep giving for wanting to hang onto the $1 bill are that it’s cheaper to make, and it’s more convenient. First of all, $1 coins are crazy cheaper in the long run. $1 bills are technically “cheaper” to make, but coins last much longer, making them a lot more economical. That’s the whole reason the treasury would prefer to make the switch, and why they are advertising the coins.
Though a coin costs about three times as much to produce as a bill, it will circulate for an average of 30 years, whereas a dollar bill lasts 22 months, and for the last few of those, has all the charm of a grimy, germy handkerchief. In 2002, the United States General Accounting Office (now called the Government Accountability Office)* said we’d save $500 million a year in production costs if we shifted to coins; another GAO document puts the savings even higher, at $747.5 million.
Convenience is all a matter of personal opinion, but I would much rather keep a few coins on hand for things like vending machines, parking, tolls, laundry, and car washes. Getting those things to take $1 bills is sheer torture, if they take them at all. I understand that men don’t carry a purse. Fine. But you have these things called “pockets” where you already carry the rest of your change.
The catch is, people have to use them. Surveys suggest that the public prefers keeping the bill, by margins that vary widely from poll to poll, but the chief hold-up is habit. Shoppers won’t use dollar coins till they see businesses taking them; businesses won’t use them until banks give them out routinely; and the banks aren’t going to invest in infrastructure changes, like new coin-counting machines, until they see the public using the coins. Everyone’s waiting for someone else to move first.
But overall, I guess this response proves my point. Until they stop making $1 bills, people aren’t going to use the coins. Most people are sheep creatures of habit, so as I said before, the only way to get the $1 coin accepted is to stop printing $1 bills.
Same source as before. Seriously, you should actually read it this time. Don’t make me link it again. 
Oh, and WTF penny? Go away.