Im working on a PHP online video store that sells video download links which are disposable and only good for 1 download. All purchases are made via PAYPAL. Once the payment is successful through PAYPAL the customer will receive their video download link via email.

My online video store offers a shopping cart and a unique feature of having the customer update the quantity amount. So if a customer wants to purchase a video with a quantity of 3, the customer have the ability to change the quantity from 1 to 3 and the total price will automatically update. Thus the customer will receive 3 seperate emails containing thier video download link.

Thats basically how my online video store works and its built entirely in PHP. After conducting a research online I realize that there ARE'NT any online video store that sells video download links the way my online store is doing it.
For example, the majority of online stores that sells downloadable files are static therefore a customer can only purchase one file at a time with NO shopping cart.

I don't know why the majority of online stores are using a static method of selling downloadable files but I would like to get some feedback from people before my online video is fully deployed.

I am open to critiques and suggestions.