I'm guessing the catering on International Business is a function of the length of the flight, just like it is on domestic first class. I believe some of the longer routes get domestic transcon-like service. IAH-AUA is quite a bit longer than EWR-SXM, but I don't know if it would qualify for the upgraded service. I believe flights like EWR-Mexican Riviera (PVR, ACA) get the upgraded service, but surely someone will correct me if I'm mistaken.