I don't know why this is being down-voted. Compare obesity in Europe, where the lifestyle is closer-knit communities where walking and public transport are viable, to the the USA and it's suburban sprawl, where cars are used to go everywhere. Cars do affect how much exercise people get.

It's the same as /u/TwistedTooth's below. Muscles maintain no more mass than they have to for the work they do. Atrophy is by definition what happens when a bodybuilder steps away from his workout regimen. His muscles are no longer receiving the stresses they need, and his body responds by decreasing his muscle's ability to bench.

Now, do most people need to bench 250 lbs? No. Even out of the gym, the amount of atrophy this former bodybuilder would see would be only until his muscle mass matches the exertions of his new everyday lifestyle, which no longer includes benching excessive amounts of weight.

The general point I'm seeing being misunderstood is that 1) atrophy means an excessive loss of muscle tissue, which isn't always the case, and 2) that those who do use this device to lessen the effort from point a to b won't see any atrophy.

As for #2, unless they increase their amount of activity to match the amount of 'free energy' provided by the device, they will see some atrophy. So the average man just looking to make his daily life easier while keeping the same routine probably doesn't want it. However, for elderly already suffering from a lack of mobility issues, which is keeping them from a regular exercise schedule, or for people looking to exert themselves beyond their regular bounds, this could be a very useful device.