Besides, there is one thing that escapes all logic.
First you should not be like a stupid hours campaigning because you may end up sick.
Second, it does not make sense for you to spend so much time campaigning to improve your items, if you then play few battles. Why do I want improved items, if all my time in the game I have spent campaigning?
Third, people get bored always making a campaign and in the end ends up leaving the game and every player that leaves the game, is a potential customer that the company loses. When do you feel more stimulated to buy? When you get bored or excited? If you open and open boxes and never get anything good, you are not being encouraged to keep going, you lose your enthusiasm and you do not buy anything else.