General

1) To absorb perspiration from our feet. It is easier to wash socks then shoes.

2) Early shoes must have been rough on the inside and must have chaffed the skin of those who wore them.

3) Extra warmth.

4) Protection from biting insects.

5) Protection from abrasions from brush and sticks at foot level.

There has to be more... anyone care to add to this list?

Sox are part of the ritual of wearing shoes I don't wear either.

Please stop right there. What you are or are not wearing is beyond the scope of this forum.

I hope next time your are not going to ask explanation for wearing briefs and pantie.

I do because my wife tells me to do it and I can give you very good non-engineering reasons why I do listen.

But you should do a controlled experiment to realize the reason for yourselves.

1) thoroughly wash and dry your feet (mother standards).

2) use a plastic utility bag, cling wrap or a condom as sock on one foot and the other without.

3) follow your normal daily routine.

4) At the end of the day measure / inspect the status of both feet. Perform all prescribed tests.

5) write a 5000 word report and submit to CR4.

6) Or . . . . . apply for a permit at your local authority not to wear socks.

Try this experiment .

1. Put on a pair of sneakers without wearing socks.
2. Spend the whole day in the hot sun doing hard physical activity that will make you sweat all over, including your feet.
3. At the end of 9 hours, remove your shoes and note what your shoes and feet smell like.

Does this answer your question now ?

A google search of "why wear socks" produced the answer.

I bet that shocking revelation knocked everyones socks off here.

To keep feet from wearing out the inside of shoes.

Of course if you regularly walk through longish grass with lots of seeds in it, you will either buy lots of replacement sock (the seeds are almost impossible to get out), you will get used to going in bare feet or wearing thongs ("flip flops") or you will start wearing sneakers without soxs.

Of course if you do a long days work wearing sneakers in hot weather without soxs you will need an extra couple of pairs of sneakers so the used ones have time to dry out and deodorize before their next use.

Make sure the "deodorizing" sneakers don't come into the house.

All of this is, of course, only vaguely relevant to the OP.