Not every investment has to be a pyramid scheme. If you are generating value or selling a product then you end up with more money than what your investors are p

Not every investment has to be a pyramid scheme. If you are generating value or selling a product then you end up with more money than what your investors are putting in. What makes bitcoin into kind of a pyramid scheme is that right now a big part of the reward for miners is the 25 bitcoin you get from mining a block. Only a very small fraction comes from the transaction fees. The only way to keep bitcoin stable is by having a constant supply of new users buying into bitcoin by acquiring those fresh bitcoins from the miners.