Price spikes can also encourage people to hoard goods.
Can you offer an example of what you mean?
What about the case of the hotel room prices cited yesterday? Normal price is $50, motel raises it to $100 when a bunch of people show up. Family of four usually gets two rooms -- one for the kids, one for the parents. With the price doubled, they decide to get one room instead and use cots thus freeing up another room for the people wanting rooms. For the people waiting it's a choice of no room at the same price of $50 or a actually getting a room at $100.
In this case there's no incentive to get a room while you can like you surmise would happen if the price spikes to $100.
Price spikes dramatically lowers the number of people who are able to hoard goods. price caps cause supplies to run out. Price spikes that are dictated by the free market eliminate supply problems.