Why there is no billing address in stripe Checkout

Billing address support is deprecated in Stripe Checkout.

Billing address is not required for merchants to accept credit cards, it does help reduce fraud rates as the merchant can ask the bank to verify the address provided with what they have on file for the card, this is known as AVS (Address Verification Service). AVS is quite a useful tool but it only checks the numbers in an address which makes it great for things like Zip Code but not as good for checking things like city or the street address. This numbers only limitation has been known to cause many issues when verifying the street address (this is why Stripe doesn't have an auto-decline on street address failure setting).

Thus given that AVS is really only useful for Zip code, Checkout only supports collecting and checking the zip code field.