Q1: that remains to be seen. I think there's a potential for it. Anyway, if it doesn't make sense, the problem will disappear on its own due to bankruptcy. However, as thearticle suggest its a growing trend, there seems to be value in it.
Q2: it's not.
Q3: well, firstly because they might not enjoy team sports. Secondly, a gym let's you excercise just the muscles you want, when you want. Playing football, for example, you don't build much upper body, so you'd have to hit the gym for that. Then you have those with sports injuries, of course. As for myself, I go to the gym to work out. I play football for fun, I have no fitness angle when playing football.
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