And McDonald's corporation largely makes its real money off of franchisees paying fees that purchase real estate for the corporation which is later sold when the franchise goes out of business. Nothing about the McDonald's model has anything to do with mobile real estate, rather the opposite they make their money as a company that disposes of the real estate for a profit rather than a business that makes money in a particular place. Many of the elements that McDonald's uses to approve particular franchise locations are actively inimical to the franchisee's success. Did a case study on this in grad school.
And sorely lacking on water outside of a very few densely populated harbors.
Not necessarily, certain purposes require purpose-built buildings, others do not.
Not really, because the center was built with the purpose of hosting many smaller tenants. That does not mean that the tenants are more rational then the landlord. It's simply a different business model.
If this were true, the market would reflect it.
Point one- yes this is often the case. Point two: there is less competition for the territory, but more cost to starting and maintaining a building upon it due to the dynamic nature of the foundation under it. Long term maintenance cost of a building in the desert is less than of a ship- Ellmer makes the point about cost-effectiveness of ships all the time. A cubic meter of "building" in the desert doesn't have to float, for years, with minuscule chance of failure to float. If you have to abandon the building in a fire your plan B requires no more than walking outside. To claim that the cost of maintenance of other floating platforms will be significantly less than the maintenance of an oil platform's flotation simply doesn't make much sense. The operational costs of such a platform would probably vary, but basic maintenance of structural integrity and buoyancy is unlikely to do so.
As for less expensive to transport on water than transport in the desert- maybe, maybe not. Cost effectiveness depends on volume as well as distance. Volume depends upon demand, which depends upon population. Shipping food for 50 people to an arbitrary point half-way between San Diego and Hawaii is much more expensive than shipping food for 1000 from San Diego to Seattle. There are hundreds of carriers taking the latter trip every day, with competition, established re-supply of fuel, infrastructure, experienced drivers, navigation aids (signs) and lots of co-terminous traffic.
Here we start to explicitly separate the cost of construction from the cost of maintenance. TCO has yet to be addressed, nor the cost effectiveness or ROI. I can spend exactly the same amount in setting up two projects, and have one fail while the other succeeds wildly. the difference would be in the profit margin. one of them makes lots of money, one makes little money.
The picture is great but lacking context. Contrast it to land-based patterns of the same type of traffic.
Overall, I believe that the ability to claim 2-D & 3-D space that no one else will fight you for is considerably greater on the ocean. You won't have to pay someone for the space, but the construction has equivalent or higher costs, the maintenance has higher costs, and the convenience varies greatly. There HAS to be some relatively closed loops of local production to make it cost effective.
Unfortunately, most of the most desirable space on the ocean IS being claimed ad fought for. Minerva, Sealand, etc. The Marinea project guys talk about Cay Sal, which has real potential, but is claimed. The Honduran reef banks- claimed (ethically or not, it's claimed). Large swathes of deserted, uninhabited Pacific Islands and thousands of square miles around them: claimed. North American continental shelf: claimed.
You can probably make your own claim to some of this and eventually make it stick, with a little luck, some lawyers, guns and money, but not without any fight whatsoever.
Best practical thing is to accept some level of de jure oversight while having de facto autonomy and play the game as much your own way as possible, without incurring the wrath of any real power.