If Bitcoin price goes high enough, I bet ya someone will take advantage of new markets which involves instant transfer services for cheaper fees. It would be ironic for BTC.
So, you seem quite sure that people don't care about security of the network and instead always select the cheaper option. I can accept that bet, how much you want to wager?
Simple fact: Imagine this person who JUST recently heard about bitcoin where its value is derived from people who buy it (currently $1,100), no banks, no government, no central entity involved. And its transferable ONLINE. Wow! Amazing!
But then it confirms in one to two days because of congestion.. And then he has to pay higher fees to get in front of a queue that will continually try to outbid one another. What do you think he'll do? Back to bank/ATM/creditcards/Paypal...
For those who actually use bitcoin on a regular basis, these will not do. If some central entity promises they will take care of your balance in any online crypto service for a smaller fee, that's a big demand already caused by the backlog. For example, Coinbase and Coinbase-connected businesses and services.