Why do I need to pay just to get free apps

Needing a form of payment is not the same as paying. You don’t need to pay to get free apps, but you do need a VALID form of payment in your account, as it can be used to verify your address, age and other information needed to set up an account. There are ways to remove a payment method if you have no apps with in-app purchasing features and no subscriptions. Here’s guidance of valid forms of payment→Add a payment method to your Apple ID - Apple Support and here is information about removing payment information→If you can't choose None when you edit your Apple ID payment information - Apple Support

The bottom line......Because Apple calls the shots.

Schadejames wrote:

Why do I need a form of payment to down load free apps?

For verification purpose as not all apps are available in every region, you are not charge to get free apps.