I am not a penny pincher but I don't understand people who would volunteer a price increase for "convenience". That money is going to profits of others to live on. Its not going to reduce your taxes, not going to pay for community inprovements, not going to quality of life.
For example. You will not see $2.76/gal. anything above 2.75 would be 2.80. and you may think this is minor but it is not. Not only will you be volunteering to pay more just because there are no pennies but competition between stations will be minimized as well. How often do you drive to a gas station a block away because they are selling gas at $2.76 vs $2.78??
It may only cost consumers a couple hundred bucks a year but it would improve profits of the big corporations by millions to hundreds of millions. I would gladly accept $.01 of every gallon of gas Exxon sells as my yearly salary.
Also, when businesses start rounding everything up to the next nickle the nickle will eventually be as undervalued as the penney. Suddenly a .10 price difference or increase may not be too much for you too accept.
Pricing is a big piece of consumer marketing. So much so that suppliers have reduced the quantity in packages where possible so they do not harm the psychological acceptable price by consumers.