exchanges are not the only way to buy bitcoin and using a bank and doing a wire transfer is not the only way of transferring money.
there are a lot of ways, one of which you mentioned yourself. accepting bitcoin as payment. it can be for selling something, offering some service or simply receiving your salary or part of salary in bitcoin. these are the ways you acquire cash, aren't they? so why not use them for bitcoin too.

as I said you can use other methods, the P2P methods to buy bitcoin. buy from someone around you.
I have someone that I always buy bitcoin from. I send a money transfer (I don't know what it is called in English, the banking system in my country is different) for free and with no delay and I receive bitcoin in return. the rate is not bad either. it is a little higher than market value which is negligible.


LOL, sounds more like another excuse to raise some funds and get rich.