Why does a cat close its eyes when drinking milk?

We have a heard a lot of saying referring to a cat closing its eyes and drinking milk.
We compare it to people who feel the world stops looking just because they can not see
who is looking.
We also refer it to short sightedness.

But do we really think why the cat closes it's eyes when drinking food?

It is vulnerable when snacking to other creatures of  bigger size.
Mostly kids throwing stones or playing cricket, sometimes dogs and
sometimes adults when the cats sneaking into the house to have a drink.

Even so, the eyes are closed

There can be a simple explanation to it.

If the eyes were open the cat might get a squint.

It's face is so close to the bowl and the tongue is also small.
Trying to look at such close distances will be like trying to look at our nose to figure out how big it is.

In all fairness, even we don't look at out morsels when we are eating
We are too busy looking at the opposite person and pointing mistakes or too lost in out thoughts to notice our hands going to our mouth and food in our tummies.