A Paypal account on a US address has three stages i.e. unverified, confirmed, and verified. Every new account is unverified. When you add a Credit Card, your account becomes confirmed, and when you attach a bank account your account becomes verified. Unverified Paypal cannot be used to shop online, but confirmed Paypal can be used. The big catch is, everything is fine only as long as you are buying virtual goods. When you buy something that has to be shipped, Paypal requires the merchant to ship to the address that is entered/selected on the Paypal website during checkout. If the seller ships to some other address that is not mentioned on the Paypal website, they expose themselves to chargeback fraud, as the buyer can claim that the seller shipped to the wrong address. Since Paypal is not available in Pakistan, it does not allow you to add a Pakistani address during checkout. This makes Paypal useless for online shopping of physical goods from Pakistan. Add to this the risk of your account getting limited i.e. frozen at any time if Paypal feels anything is wrong. The only way to remove the limit on a limited account is to confirm your id and address by providing government issued documents, which wouldn't be possible on an account registered with fake details.
I once had to receive a payout from someone who would only pay to Paypal, so I created a Paypal account and got it confirmed by adding a virtual credit card. I tried shopping at Banggood, but they cancelled and refunded, citing the risk of fraud. However, shopping at Gearbest went just fine. The bottom line is that the only time you would do this is when you have money stuck in Paypal. I don't see any reason to load money into a Paypal account from Pakistan and then face all the troubles.