Fees are not necessary for the processing of the transaction on Bloakchcain but it gives extra priority to incentivize miners for processing transactions faster in the block.
Fees are necessary!
Imagine how the mempool would look right now if we didn't have fees!
If there is no fee, the mempool will completely be congested. The fee is even the hope in the future when all bitcoin are mined.
More transactions => larger data size => more workload. Imo, when the network is congested and over-loaded, miners have to work extra hard to include each of those transactions in the block and for that we need to pay more fees to help them cover the cost.
There is no such thing, a miner will do the same amount of work for an empty block and a full block, there is this misconception with the transactions numbers or size or fees require something extra from the miners when it's not the case. Also, it's a bit silly, what "extra" work would miners have to do for this and how would they even do it?
[/quote]
There is no extra work at all. But maybe extra profit as people will pay higher transaction fee.