The idea of offending someone is irrelevant, really. You can love whoever you want, believe whatever you want, say whatever you want, but it's always going to offend someone in some way or another. The only thing that pisses me off about "touchy topics" is simply when people are illogical in the way that they explain why they believe what they believe. There's a great difference between offending someone and offending someone in a blatantly ignorant manner.
You fucking bitch-horse of an ignorant faeces-brained piss-bottle. Do you have no idea how orcishly ignorant a californian blond-worth post that was? Or that the idea of anything not being wrong with offending people is positively arachnidian in it`s venomousness and it`s revelation of the complexity of the neurological processing behind it? What would be the exquisitely Game of Thrones-esque fun in it otherwise?
But back to the real world: That kid who found it disgusting, was attempting to be offending otherwise a different wording would have been used. That is where you describe his disgust as idiotic and continue the discussion.
From what I've seen and from personal experience, finding something (truely) offensive relies on the inaccuracy, the belittlement of a group with no effective counters, how common the incorrect thought is, and/or poor intentions as perceived.
As for when it is right or when it is wrong, my common rule of thumb is if you are trying to make someone or something lesser than it really is. If you just want them to laugh at their human flaws (and even share with them,) then it isn't really bad. And trying to base something off of reality as best as possible (the Arabian jocky in the Super Bowl Coke commerical) or use something that can get idea from people correctly without belittling (the Jamacian accent from the Super Bowl Volkswagon commercial,) then I find it find. But it is when you want to offend someone so others may laugh or to try and gain in your political war, it isn't fine.
I don't think offending people is a bad thing in itself either. Like you said, some people will be offended by two men or two women kissing or getting married or basically being happy together. Or people practising a faith other than their own (or having no faith at all). I also know that some people will be offended if I voice my opinion on certain topics. There is for instance no safe way to go wirth abortion. And I'm (mostly) cool with that, let those people be as offended as they want to be.
What I do care about though is not minimizing people. This is why I often check my own language and have somewhat neutered it. It's about not reducing people's sexuality, nationality, disability, or other characteristics (they often have no choice over having) into a punchline or an insult. Some people call it political correctness, but I think it's just about being a decent person and respecting other people. It's why I don't call people retards, and I don't call things I don't like gay.
It works twofold how those things can be hurtful: If someone's called gay he can either be offended because he considers being gay a bad thing, or he can be hurt because he is, or knows someone who's gay and knows that I think being a gay is a thing worth insulting someone over. We still live in a world where those words can have that negative meaning, and that's not something I want to be a part of.
I had a really long answer for this, but then my browser crashed so fuck it.
Short answer: There is nothing inherently wrong with it, but if you're "offensiveness" is an act that is actually problematic IE hurtful to society or someone important, that's probably when you should do a self-evaluation of your action.