Honestly, one of my waterloos is Labor Laws.
To provide an answer to the issue : What is the legal basis for an employee to demand for transportation and meal expense from an employer? (I exclude hazard expense) I will say:
Laws on Contracts: when said benefits are included in pre-employment agreement (as compensation package) or the giving of the same is included in collective bargaining agreement, that is the legal basis; since stipulations of the contract are the laws between the parties. However, if there is no contract that covers the same, no labor standard law requires an employer to give such benefits. Thus, if your American boss did not agree to pay for the transportation and meal expense, you cannot compel him legally.
I excluded hazard expenses, because I have no idea what hazard expenses cover.