For those of you who find this post too long just read following 2 sentences and move on:
Be very careful when investing in exchange tokens for unknown low volume exchanges. Most of them are scam and you should stay far away from them.
I have recently watched a video from Data Dash
https://www.youtube.com/watch?v=85D9dyUytwY about Fee Mining. IMHO he is very down to earth crypto youtuber and I would recommend that you watch some of his videos if you are interested (granted his channel is more for beginner audience, but this video I recommend for everyone).
In short Fee Mining has no connection to classic mining. It just means that an exchange is giving back a part of transaction fees to holders of their token/coin. This has become a next big thing in crypto. It seems that every exchange, no matter how small or obscure, has to have it's own token. I am not buying it, they will just perish in flames.
I am not saying all the exchange related tokens are scam, but keep in mind, there is one Binance and there is a shitload of unknown exchanges with very small volume of trading. In the video I linked above CoinBene has been used as an example of this bad practice. You can easily see that they have artificially pumped their volume (market makers volume - check this
link of my previous post if you need explanation) just to incentivize a lot of people to invest into their token which has very quickly lost a lot of its value.
There is quite a lot of similar cases out there. If you have been burned by some of them please post so I can add it to OP with due credits.