You could consult the law, INA section 212(a)(2). The pertinent part reads the following:
(i) In general Except as provided in clause (ii), any alien convicted of, or who admits having committed, or who admits committing acts which constitute the essential elements of—
(I) a crime involving moral turpitude (other than a purely political offense) or an attempt or conspiracy to commit such a crime.
Crime is generelly defined by state law. Shoplifting in some states is a crime, thus of moral turpitude. However your friend only got fine and taking lessons, which indicates that the shoplifting in your friend's state is not a crime, but a violation.
Beware that the immigration officer always has discretion to determine what is crime of moral turpitude. The best way is to hire a lawyer, not a chinese lawyer, for the interview.