Is it safe to wear reading glasses even if you have perfect vision?

Yes! Perfect is relative. You may have perfect uncorrected vision at distance but some presbyopia or difficulty with focusing up close. Readers are recommended. You can't hurt your eyes with them.
Safe but why? Reading glasses are used to compensate for the natural loss of near focus in those over 40 years of age. For those younger, they are not needed so the question is why wear them at your age when they are unnecessary.