This is what you should do, disclose this incident because I am certain that USCIS have access to this information. If a traffic ticket appears in court records, which is less egregious than a shoplifting offense, do you really think telling the judge NOT to your record on public file is going to happen? Irrespective of your own background check, FBI has more tools than you actually realize and USCIS knows that this record exist, and this is a fact. If you have a chance of heart, decide to NOT disclose this offense, an IO will interview you and let you perjure yourself, resulting in a denial of your case and being barred from naturalization for a while.
Your case has 75% chances of being approved with full disclosure of your criminal case, because you qualify under 'petty offense exception. However, an attempt to conceal your run-in with the law, will actually get worse. Also, remember that USCIS can still nail for fraudulently obtaining US citizenship 20-30-40 years from now. It has happen to many people who lied they way into US citizenship.