yes they are ,one reason is that paper money is cosily to make two plain paper is a lot cheaper to make. also coins are heaver and more costly to count them where paper is counted by machines.

They are all getting rid of coins.

Mechanically there is so much more to go wrong, and lugging all those heavy coins around is a pain.

yes they are easier to maintain..less chance of a mechanical breakdown much harder to cheat
i hated whne your getting paid out and the machine would run out of copins.and had to wait around for an attendent come and reload the machine so you can get your last few coins
also it is a pain thet they come around and want to refill your machine..while your playing it