Quick answer
Taking from your parents and calling it nothing puts you in the same category as a wrecker. The verse targets the excuse as much as the theft.
Read both lines
Three lines, and the middle one is quoted speech, which the book uses when it wants you to hear a person's own justification. It is no transgression is the whole defense, and it works by reclassification rather than denial: he did it and has decided it does not count, because the property was family and the family was going to be his eventually.
The verdict is the third line, and it does not call him a thief. It calls him חָבֵר to a man who destroys, an associate, which is the same move 26:18–19 made with the man who said he was only joking. Both verses treat the reclassifying excuse as the more revealing act, and both answer it by naming the company the speaker has joined.
Related: Proverbs 26:18–19 · Proverbs 19:26 · Proverbs 20:20 · Proverbs 30:17
New King James Version®, Copyright © 1982, Thomas Nelson. All rights reserved. Full copyright information. Scripture provided by API.Bible.
Go Deeper
If this verse has been used to put weight on you that it was never carrying, ask about it directly.