Is a db really necessary here?

Say I have a simple shopping page, with a pic of a product, link to it’s description page, and buy button. I also want to have a page where people could easily add a product for this page, along with a pic for it, and a description. This page would then take the submitted info and add the new product to the products page.

A db wouldn’t really be necessary here right? Or would it depend on how many products you have? For example I have 50 products, 10 per page. Would it be possible with php to just add a new product to “the end” of the current products, without having to make a db connection everytime someone requests a product listing? Or, if a db would be better to use, would it be possible to just generate the page once from the db, and then for subsequent requests just serve up the already made page?