The science department sent this answer;
In most blockchains the baker / miner / validator gets the transaction fees corresponding to the transactions in the block that they create. In Concordium, we give “only” half the transaction fees of the new block to the baker, but they also get 25% of what is in the GAS account. The other 50% of the transaction fees for the new block go into the GAS account. The effect of this is to even out the transaction rewards between all the bakers. For example, if there is a block with very large transaction fees, it doesn’t all go to one lucky baker, but gets shared with subsequent bakers via the GAS account.
I hope it does answers your questions.
Concordium Tech Support and Science team.