They can only be trade at ETH in uniswap as I know. So if you want to keep the fee down you use metamask with a friend. You send your grunt to same metamask and make one big swap. That is the only way I can find out - but I am not an cryptoexpert.

One other way is to use grunt to buy pigs and try to sell them at discord. That is obviously not so easy but I have sold some.

You can only withdraw if you have at least 500 000 grunts. Then it is no problem to pay 5usd in withdraw fee and 8 usd in gas fee. I did get 50 USD in eth for 100 000 grunts.
But the value go up and down as all cryptos and tokens

you have to pay a uniswap fee of 8 Euro for every swap, and you can't exchange 500.000 grunts at once, therefor until you exchanged everything you need to pay way too much in fees. that alone is a put-off

And now the value is to low so you get nothing from it.
Still - the first trade I did was Good.
From piggericks to eth gave me 50 usd for 100 000 grunts after all fee