Apologists for the mobile home industry will say they use a different philosophy in design where every cubic inch is used in the most efficient way (similar to boats) so some rules we have in stick built homes should not apply to them. They don't want to talk about the fire statistics and the lower standard they have for insulation. One reason why they seem to have overly large services is that the HVAC system can be twice what you would have in a similarly sized house. The other problem is they tend to grow out to the edges of the property line with "cabanas", sun rooms and other site built additions, seldom permitted or inspected. These all get added load from the service.
When inspecting hurricane damage, you find these additions are the first thing to go since they are generally aluminum, vinyl and glass affairs, put together with sheet metal screws. They seldom meet any similance of a building code.
