Opening a Fulfillment Center in New Jersey

Amazon.com is looking to facilitate its same-day deliveries in the New York City area by opening another 1 million-square-foot fulfillment center in New Jersey.

It's actually their second fulfillment center in New Jersey, the other one being in Robbinsville. Incidentally, New Jersey is one of 24 states in which Amazon must collect sales tax. Merchants in these states have to pay a sales tax in addition to the fee Amazon charges to use its website and storage facilities. Are these merchants at a disadvantage because they have to pay both the sales tax and Amazon fee? Would they be better off selling their products in a state that doesn’t require a sales tax?