If you do mining for your own transaction, you don't need to pay transaction fee. If you ask others to mine for you, you're not a direct member of the blockcha

If you do mining for your own transaction, you don't need to pay transaction fee. If you ask others to mine for you, you're not a direct member of the blockchain network. The additional cost to incentify others to help you depends on the demand and supply. If many people wants to develop their own app but not able to program themselves, they may hire developers to serve them, but if the global population are relying on a few developers, they either have to wait for a long time, or need to pay more to get "premium service" in higher priority (and making others paying less to wait longer because the throughput is mostly fixed)