I do agree that arcade generation is getting older. And the first thing that comes to mind is the diner scene in Back to the Futrue II.
Marty McFly: [showing the two boys how to play the shoot 'em up video game] I'll show you, kid. I'm a crack shot at this.
[shoots a perfect score with the electronic gun]
Video Game Boy #1: You mean you have to use your hands?
Video Game Boy #2: That's like a baby's toy!
And the fact that the story takes place, at least partially, in 2015 is kind of interesting as well (I am still hoping for a Hoverboard!). But will this be the end of arcade cabinets and mame? I don't really think so. It will become even more of a niche hobby over the years. Our kids nephews, and nieces will grow up with arcade cabinets. It will be part of their childhood. And they will invite friends. I believe that while arcade games in stores and malls will grow fewer over the years, but not in garages and game rooms.
When I first saw an arcade machine, I just stared at its beauty (If I remember correctly it was Final Fight). It was easy to understand, you had to pay for the right to play it and that was part of the beauty. It wasn't all graphics. It was all about the experience that simply is not the same on a PS3 or a XBox360. Not that these consoles are bad. It is just a very different experience. And it made you feel like an adult. You were in control and not only of the game. You paid for it. You decided what to play with your quarter. This is exactly what I intend to do with my children. No, I won't take money from them.

I will give them some tokens (maybe 5 or 6) and just let them play. There will be occasional free play times. They'll play games and will learn how to spend real money.
In my opinion, this is what makes this hobby so especially enticing. For us it is the nostalgia of our childhood spent in arcades and for the next generation it will be the nostalgia of the kids' time spent in game rooms and garages. As eds1275 said, you don't have to spend a lot of money. It is basically a hobby that is like most of the classic games: "easy to learn, hard to master".