Why do some cars only have a physical lock on the driver side?

I have a car (tsx) and I realize that sometimes I will need to use the physical key instead of the electronic key fob to unlock my car. Such as if there is something wrong with the electronics or my battery died. But then I realize that on the passenger side of my car, there is no key hole for it!

I also rented a car (mazda 2) a while back and that car did not have an electronic key fob to unlock the door remotely. I went to open the door first for my wife, but then I realized that there is no lock hole on the passenger side! I had to unlock my driver side door first and then unlock hers from the inside.

Also, something has went wrong with the electronic trunk button inside my car, so i can only open my trunk using the key fob. Why isn't there a physical lock on my trunk too?

Why doesn't my car have a physical lock on the passenger side? Is it just because car manufacturers are being cheap?