I *think* the question being asked is if when coin generation for found blocks goes away and pools/miners will only accept transactions with fees how high will the fees go -- if they will be 5-7% or higher such as other methods of payment.

The answer to this, from what I've read, is that the network will set their own limits at that point. Some miners will still take free transactions, while some will set to only take transactions with X, Y or Z fee, and just depending on how much your fee is depends on how many miners will include that transaction in their block, thus lowering the possible time your transaction would be unconfirmed. This is as I understand it, which might be incorrect.