While Thailand is the Land of Smiles, you really should be cautious of anyone who approaches you "out of the blue", irrespective of their nationality. Encounters such as these can potentially lead to you becoming the victim of a scam or con artist. Don't simply trust a stranger based solely on the fact that they're from your "home" country. Con artists of all nationalities are "out there" scheming and cheating their way through life. Thai people can be very helpful and accommodating when asked, however it is not a normal Thai custom to approach strangers and offer unsolicited advice or assistance.