I don't think anybody ever responded to my comment, so I'm going to make it more clear:
DDR is a <u>fitness game</u>. That is exactly how it's advertised. Why do you think they brought DDR into schools? For what other reason would it be accepted into local YMCAs? What about all these weight-loss stories? The point is to get kids physically active and get some exercise.
The problem is, anybody who isn't absolutely terrible at DDR won't ever break a sweat on even the hardest songs. I'm sorry to be blunt, but DDR is not a physical game to people who know how to play correctly. Sure, I could bring my knees up to my chest for every step and waste that much more energy when I play Cowgirl Heavy but then my score would suffer. You can't PA when you're prancing around like an idiot, and to anybody who takes the game seriously, score is a very important issue.
The obvious solution is to make harder charts so that the advanced players can also reap the physical benefits of this so-called fitness game. I honestly don't understand why people are arguing against this. You don't have to play the charts if you don't like them. They could even be on a separate, new difficulty for all I care. But the better players need something to keep them playing the game, and quite frankly, the difficulties we have going right now aren't even close to doing it.
Oh, and please don't act like playing no bar will fix anything; that hardly makes a difference for the better players. I still don't break a sweat on the 10s from playing them no bar.
Guys, this is the reason Konami loses so much popularity among the advanced players to ITG and PIU. It'd be a really easy fix. Just make some new hard charts that are actually tiring. That's it. All the people who are whining about how they don't like difficult charts would still play the 7 and 8 footers that they like, so I don't see how they have nothing to complain about. No matter what, they can still enjoy the game since it still caters to their skill level, so this isn't even relevant to them.
Short version: If you actually care about the fitness aspect of DDR, then please provide a means of exercise to those who aren't ridiculously overweight, out of shape, new to the game, etc.