Will not make a difference to anyone as you are still going to USE gas that day, who cares if you don't buy it one day.
Its like if a bill comes out of your account a day late, Are you going to freak out and rush to the company to ask why it was a day late.
I think if everyone there didn't use gas for a year or so then it might make a difference but seeing how most internet protests are done by people to lazy to get off their *** and do something I highly doubt they would inconvenience themselves by riding a bicycle, walking or taking the bus to work for the next year.
Too many people these days think they can change the world by posting a couple paragraphs on a website and doing nothing further to help their cause.
To the oil company giants even if every single one of those people didn't use gas on a certain day, It would be like being $0.10 short on a normal workers paycheck.
Are you really going to care and try to figure out why it was short $0.10 or are you just going to go on with your day.