So when mining we actually calculating other people transactions. What if everone just mining and nobody make transactions? The whole point of bitcoin is that it has no fees if you use professional mode wont that defeat the purpose of not having a central computer? And after 2140 there will be no reward to maintain the network then why would anyone bother doing it? Would the people investing money into these servers not just quit right away causing the whole system to collapse and the value of money be completely lost?