In pretty much every single other business, what Uber calls "surge pricing" is referred to as "price gouging," and is illegal.
What's the difference between what Uber is doing today and what a handful of gas stations tried to pull on 9\11\2001? The fact Uber is getting away with it?
Cite? If it is illegal, then you can reference the law.
In any case, making demand-based pricing (or gouging if you prefer) is often counter-productive. If a resource is scarce, you WANT people to change their behavior. If there is a hurricane and gas is scarce, then you want people to stop driving to the movie theater or whatever, and then there is gas available when people need to buy necessities or whatever. If you have to drive to the hospital, you're not going to care if gas is $10/gallon. However, that $10/gallon gas will prevent you from driving to your friend's house to hang out 25 miles away.
The alternative is that everybody runs out of gas, and then people with connections get their cheap gas, or you have wasteful activities like driving 100 miles to buy gas (thus wasting quite a bit of gas vs just tankering it in). During Hurricane Sandy there was quite a bit of scandal where people with connections got cheap gas from FEMA depots, and then everybody else just did without.
The exception should be situations where there isn't much competition, and there should of course not be collusion. That is just antitrust law.