......Yet!!
What you said should be a concern to everyone....they may begin to associate humans with food. It might be 10, 20, even 100 years from now but after they mistakenly bite enough people they could very easily realize we are, in fact, edible. Pavlov's Law will eventually kick in. If I touch something and cause damage to the ecosystem I may not see the effects in my lifetime. Does it really matter then? If so, this remains a dangerous tourist attraction since there's insufficient data to show that what I'm talking about WON'T happen. Granted, I could be wrong.....agreed. However, if I happen to be right, eventually they'll be touching us!!
Just like touching, interaction should be done responsibly. I don't think feeding sharks is responsible. They're predators...let them seek out their prey, not be fed like pets.
On a side note, excellent discussion thus far. Some great points from many people and a few things I wouldn't have thought of.