I think that this will happen soon, because taking bitcoins by sellers will lead to higher prices for goods because of high fees. For small purchases, this decision will be very unprofitable.
Yes this condition is not very profitable, so try to buy maximum amount of bitcoin or if you want to sell then try to sell maximum amount of bitcoin, because in this way you fees will no effect you profit and you will get what pretty much secure future for you bitcoin, and I hope sooner when retailers accept bitcoin then this profit margin will increase further more.