As a humanist and atheist, I have learned that what I say is not tolerated by quite a few Americans. I understand that some people would censor what I say if they had the chance.
There is case after case of atheists/ humanists -- who put up billboards and ads on buses -- who then suffer from members of the Christian right vandalizing those ads. Indeed, ads have been stolen. When not vanadalized and stolen, there has been pressure applied to governmental officials to have them removed.
Indeed, governmental officials themselves have tried to get them removed. For example, in Westminster, California (outside of Los Angeles in Orange County) Mayor Margie Rice stated:
"That billboard is going to turn my stomach every time I drive by," she said. "But there is not much I can do about it. I guess it's fine to make a statement, but if I could help it, I would not allow it."
She also stated she will ask the city's legal council advice on options. The "offensive" billboard states what exactly? Well, "Don't believe in God? You are not alone." That's it, not a statement critical of theism or Christianty. In other words the message sent is that atheists should shut up, and if they don't than governmental officials will try to get them censored. The city attorney should point Mayor Rice to a copy of the First Amendment that gurantees freedom of speech. Yes, it makes no exceptions for those who don't believe in a god
In British Columbia, Canada, local atheists there have put up ads on buses in different parts of the province. In one town, atheist signs were stolen at night, with the possibility being it might have been an inside job by those who work or provide security for the transit service in that town. Drivers have refused in some towns to drive buses with ads.
Look, there are hundreds if not thousands of atheists in the U.S. and Canada who are driving buses with religious ads that they do not agree with. They have a job and they are required to do it. No atheist I know of has refused to drive a bus with a Christian ad, so Christian conservative bus drivers should and must abide by the same standards.
Also, why do atheist organizations have to go to court in order to have ads (that they happily pay for) appear on buses? No theists have to do so. Atheists don't require government promotion of their beliefs, such as "In no god we trust" on our money. Now, to those who say why do atheists even bother because a god they don't believe in can't affect them?
That's true, but there are those on the Christian right who do believe in that god and who oppose gay rights and who wish to involve the government in the nation's bedrooms, because of the god they believe in.