bkeaton,
You didn't need to disable that button for it to charge shipping.
You're just completely misunderstanding how the Express Checkout Shortcut method works. It take the customer to PayPal to login and specify HOW they're going to pay, and shows them the cost of the CART contents. (They see a "Continue" button, and NOT a "Pay Now" button, because it's not time to pay yet.) It then returns the customer TO YOUR STORE (now armed with their address) to select shipping and calculate taxes and offer coupons and gift certificates to be applied, if any. And THEN they confirm payment on the last page of checkout, just like with any other module. They're not "charged" until that last stage where they confirm the final price.
But, if your customers are as confused about how it works as you are, then it's probably best to leave the shortcut button disabled for now. Some customers "get it" fine. Some don't. It's different in various demographics.
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