So say you are a business selling online and you have a simple button to check out for one item, then yes, you can create these buttons in Paypal and get the shipping address.
But if you have a custom cart...
<input type="hidden" name="cmd" value="_cart">
... and you want to make sure the user enters a shipping address, you need to request it. All you need to add is this line:
<input type="hidden" name="no_shipping" value="2">
The user will see a checkbox next to billing address, that says "Same as Billing Address".
If they want to send a different postal address, they can untick and fill in form.
By not asking for it on your website, you save registered Paypal users from having to unecessarily fill it out. It will be saved in your Paypal account transactions, and you can print packing slips from there too.
Enjoy!
