Tbh I would buy all of that if I was gonna hit big and get rich. But it's definitely not for everyone.
Most groups who specially come from smaller agencies go through that when they are rookies. Groups from bigger labels at least have it bit easier, they can have their smartphones for example or do not have trainee fees.
Like Gfriend didn't have their phones until after navillera despite having 29 music show wins. They didn't get paid until 2017 either, despite being very famous.
If you check them now they have lots of freedom. Instead of a dorm they live in 2 buildings with a separate room for each member, do not have to diet anymore and visit their families more often/ can enjoy their time outside.
The darkest part about it is knowing that most groups from small labels don't get as lucky as Gfriend and they have to live same way as rookies even until their senior years. Stellar for example said that they are still leaving a rookie life in their last years......