Back in my day if you wanted to work out climbing stairs you'd climbs stairs. If you wanted to ride a bike, you rode a bike. If you wanted to run, you get the picture. Now you have to pay for a gym to get on a machine that's plugged into an outlet.
Meh. I pay for the convenience of having everything in one place.
If I had to go to one place to liff, and drive somewhere else to walk up and down stairs, id never do it.
Besides, its called evolution. Theres nothing wrong with machines that simulate activities that can be done conveniently in one spot while entertaining oneself with TV, music, or working out with friends.
Theres a reason its more popular to do this in a gym environment, rather than seeing people going uo and down stairs at your local stadium or skyscraper all day.