Also, once the precendent is establishes that an ad is pulled because metaphysical claims cannot be substantiated, it becomes easier to challenge future ads. Most economists teach a theoretical framework that has been shown to be fundamentally useless. -- James K. Galbraith
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The 'it offends my sensibilities' claim is more effective. However, this is an organisation uttering its viewpoint, not a company trying to sell some product off the back of controversy slash offended sensibilities. Probably their freedom of no religion / freedom of speech will weigh heavier.