Free speech is not freedom of consequences. Anything you say can and may be held against you regardless of your right to say whatever you want.
I agree in theory here. I think the problem is the university using off the clock behavior to dismiss them from their jobs, which in my opinion is equally in bad taste. I also see a lack of humor starting to creep into america, people are becoming afraid to express themselves for fear of offending someone, being socially ostracized, or legally punished. I think while this is a minor occurance it is a symptom of a growing social problem, that being the political correctness movement.
Some things are in poor taste. Personally I think this is making a mountain of a molehill but I can see where others might take high offense. Had they gotten a replica of a female and pretended to be rapists raping her that might piss me off. Had they gotten a doll and pretended to be child molesters I'd certainly question whether they were fit to be advisors.
Your examples as noted would certainly be in poor taste as well. I think that people need to understand however that there is no right to be unoffended in this country, thus this expression, no matter which side you are on, should be protected. I don't know as much about your examples, it would have to fall under the SLAPS(serious Literary Artistic Political or Scientific value) test as defined by the supreme court, otherwise they could be considered obscenity.
These kids pretended to be terrorists who behead. Since they used a rubber duck I personally am inclined to laugh it off but not everyone draws the same conclusions when deciding exactly where the offensive line is drawn. Certainly what they did was in poor taste and if their employer feels they should be fired that is well within the rights of the employer. Had they pretended to be KKK members and the rubber duckie was black instead of yellow would that be worse? I do think there are levels of poor taste and most likely I'm not too offended by this because it is highly unlikely I would be beheaded by a terrorist but I imagine if I personally knew someone who was beheaded my tolerance for such immature displays would be much lower.
True, some people may take it the wrong way, but that could pertain to any expression. For example, it might offend me if someone said "nice day isn't it?" after I just got served divorce papers, or fired, sued, etc. It may offend me that this person is having a great day while mine is going straight to hell. While I realize that that was an extreme and very silly example I have seen people react like that(seriously) and it is merely to demonstrate that offense is an intensely personal thing so to punish people for this personal displeasure sends a dangerous message in my opinion. Personally, I think people need to laugh more and be offended less, but to each their own.