RIPE for example actually sold IPv4 classes at some point so all those are actually owned by their respective owners and can be rented out or outright be sold. In order to be able to use any of these RIPE IP spaces all you will need is to have a valid PA account/membership with RIPE and you can use them anywhere and not only in EU.
Please see this page for more information. https://en.wikipedia.org/wiki/Regional_Internet_registry
(Also, the question was rhetorical - I know how that idiocy happened, and I expect that most people here do.)
(edit: and the first one of those is causing lots of unnecessary pain, not only to travellers who suddenly have to deal with a "different internet" simply because they moved their body to a different place on the planet, but also for people in multi-lingual countries, who regularly have to deal with moronic websites forcing them into some particular language version that supposedly is the "language of their location", ignoring the fact that the user not only doesn't understand the language, but specifically tells the server via appropriate headers which languages the user understands.)
Microsoft has been purchasing blocks of IPv4 space (they bought some off of Nortel a few years back). Obviously they don't have enough.
China is under an Asia-Pacific registry, https://en.wikipedia.org/wiki/Asia-Pacific_Network_Informati... and from a link off of that, https://www.apnic.net/publications/research-and-insights/ip-... they have 44 /8s plus a /12 from their initial allocation, plus some "ranges from the IANA recovered pool"; according to the Wikipedia article they were the first Regional Internet Registry to run out of /8s.
I would assume that's bad for business.
You could use name based virtual hosting in case of plain HTTP (though there are still clients around that don't send correct host headers), but if your customers use HTTPS, you'll need one public V4 address per site because SNI still can't be used reliably.
The next round of cloud price cuts could well be for ipv6 customers only...