There are a lot of reasons to eliminate Antibiotics from environments outside of a healthcare facility. For starters, Triclosan isn't very effective, there are better options. Second, it promotes antibiotic resistance among bacterial populations. Third, if it gets into your bloodstream, it could start killing your normal flora, increasing the likelihood of opportunistic infections or gastrointestinal problems. These are just the basic reasons most college students can find. There is in doubt in my mind that there are more issues. The ban is reasonable in my opinion.
This also doesn't even mention the fact that using antibacterial soaps or alcohol hand sanitizer on kids weaken their immune system later in life, encourages the genesis of super bugs (this is actually a medical term now) such as MRSA. Also, one bacterial resistance can also lead to another, meaning if they develop a resistance for Triclosan, bacterial colonies might be able to develop additional resistances when faced with a different antibiotic. Lastly, these soups do nothing against endospores, some gram negative bacteria, eukaryotic pathogenic organisms, and naked viruses. At best, it gives a false sense of cleanliness. Washing your hands will simply rinse off most of the organisms on the surface, limiting their ability to proliferate and grow. You will almost never kill all the bacteria on your hands, because in order to do so, you would need to subject your hands to harsher treatments then your cells could allow.
Also, don't think that you need to kill all the bacteria on your person... You swallow trillions of viruses and bacteria ever time you go swimming. The human body is 10% human cells, and 90% bacterial cells (there are ten times more bacteria in your body then you have cells). Without bacteria, you couldn't synthesis certain vitamins(vitamin K is an example), you would constantly have diarrhea, you wouldn't be able to digest your good well, and you would be open to infection by opportunistic organisms (yeast and some E coli. infections are examples of this).... Just wash your hands when you need to (such as before and after handling food, or going to the bathroom), take a shower every day or two, and don't freak out.