So you think that being a decent and respectful human being isn't a priority? Sure, lots of people might not be offended by it, but it's probably better to not test it, than to be potentially kicked out for wearing something offensive. Besides, you should know better than to wear a shirt that says FUCK in public. If you don't, then you should probably go outside more often.
Word certainly have power, but it's all within context. I'm really tired of people not getting it's all about the context. The context of this shirt is a joke, and the joke is so obvious, it's smacks you right in the face. Now, if I went on an angry rant against a person, then printed a t-shirt saying "fuck *person*", that's a different context. I may start typing random words, and because there's no context, it doesn't have any meaning.
As for respect, you're supposed to earn it. Most people who shout about respect are really shouting about acceptance. As for your last argument, I could just as easily turn it around and say if you're offended by "fuck", you should get out more. If a word, however foul you perceive it to be, directed at a third party you're not at all familiar with offends you, you should take a step back and think.