There are two reasons to look at a small spot on the target.
1. "Aim small, miss small". When you snap your eyes to a precise place on the target, you can train to make the dot appear near that spot and your bullets end up where you look.
2. Target focus. It's harder to focus on a big brown thing than on a small part of it. And it's easy to get drawn in to the dot and start following it with your eyes instead of looking where you want the dot to stop.
This is not as easy as it sounds, and even the highest level shooters are working on doing it more better.
Why don't your eyes work that way? Are you sure it's not possible with some work? I like putting a white paster or piece of black tape on targets for this sort of practice.