By logic, a Malaysian entering Thailand should be able to bring any amount of money as long as they have a return ticket since we're just a neighboring countries. Even if we have like only RM100 or 1000 thb in our pocket, since we can just ride a bus or train around that price. The only reason for Thailand to enforce the rule was so that there won't be travelers, especially European or American since they're far away from the country, begging on the streets of Bangkok for money to go back home.