Terry is correct. Their natural habitat is very dry almost year round. This is why Rain Frogs remain burrowed to remain moist. They Aestivate for nearly a year before the rains come and wake them from their slumber as the water seeps down into their burrows.
If they didn't prefer dryer climates then they would not live where they are. So which part of Terry's statement was untrue? Chubby frogs such as Painted frogs do live in tropical regions just as the Tomato frogs do.