That's an interesting point. The core reason why shipping costs were pulled out separately is that it allowed the customer to choose between various options fr

That's an interesting point. The core reason why shipping costs were pulled out separately is that it allowed the customer to choose between various options freely, if they needed it tomorrow vs. whenever. If there's no choice, there's much less incentive to do that. However, there's still at least a little something I can think of; shipping is generally not part of the sales tax. Rolling it into the price means you're also making your customers pay sales tax on it. That depends on whether you've got to pay tax on the item in question, of course, which varies every which way.