Someone should invite that economist to a modern rock climbing gym. Then explain every piece of technology that made those wall designs affordable and commonplace in most major cities. Being able to train in state-of-the-art facilities, focusing exactly on the moves you need to make, day and night, rain or shine, that's crucial.
Eh, I'm not too sure about that. Plastic is a poor substitute for real rock, and seasonal climbers experience a noticeably marked atrophy of outdoor climbing ability during the off-season when they are limited to gym climbing.
