Keurigs are amazing because I'm absolutely the laziest person when it comes to making coffee. It's quick, and it gets me out the door in the morning.
There are some very obvious downsides, as mentioned in this thread, but the convenience alone makes up for it IMO.
I don't even see how it is more convenient besides the fact that you have to use a filter in regular drip coffee. You can buy drip coffee makers and program them to have coffee in the morning.