Building codes for mobile/modular homes did increase in the early 90's. Old code required the home to withstand 90mph winds. The current standard requires 130mph. Most of the homes destroyed were older homes that didn't have to meet the newer codes. The average home built now has over $500 just in hurricane hardware (straps, buckets, clips, hold downs, etc) in it.
Yes you could build a safe home for the same price or less. It might not be as big or have as many ammenities, but it would be safe.
Also $24,000 may be for the unit itself, it does not include the cost of tranportation, permits and fees, and supports or ties downs on the site. Also, you are renting the land most probably.
So for comparable costs, you could build a small safe home on a small lot for the same money.
You may not have community ammenities like a pool or clubhouse ... but this is what I mean. All these things are TRADE - OFFS for safety. People are simply gambling that their number won't come up .... or that someone will come along to bail them out financially if it does, assuming they survive.
It's borrowing from Peter to pay Paul, our national mentality.