Yakov Avinu was known for being truthful and honest. The commentators say that because a Tzaddik does not steal. Therefore, Yakov went back to retrieve forgotten small packages.
Rabbeinu Bechaye claims that the reason Yakov’s name was changed to ישראל, was in order to remove any stigma that he may have had in order to outsmart crooks like Lavan and Eisav.
In Eisav’s case, he even used the words, ויעקבני זה פעמיים, implying that he was deceived by Yakov two times. He was referring to his selling of the birthright and Yakov taking away his blessing.
Being able to be smart and avoiding being cheated by dishonest people, does not diminish from one’s pursuit of truth.
It is always important to have integrity and high moral standards. It is not a Mitzva to allow oneself to be taken advantage of and degraded. This we learn from Yakov/Yisrael, the man of truth.