In Snow Crash, a franchulate is a cross between a franchise and a consulate. For this to make sense, a brief description of the political system of Snow Crash must be given.
Most national governments have gone bankrupt or are not capable of governing. Thus, private orporations have taken their place, providing quasigovernmental roles for a fee. Within the confines of the corporations property, they act with governmental powers.
The Franchulate is the property where the business acts as a government entity. Most franchulates also provide goods or services, and also allow citizens to stop there for refuge (and in Snow Crash, refuge is quite often needed).
While the main requirement for being part of a citizen of a quasi-government corporation is paying cash, there are other requirements. Many of these are racial. To be a citizen of Metazania or New South Africa, you must be black or white respectivly.
The franchulates, from what is described in the book, can stretch from a single building to several dozen city blocks or more.
Some of the other prominent franchulates belong to NovaSicilia (which belongs to the Mafia and specializes in delivering pizza); Mr. Lee's Greater Hong Kong, which specializes in information and techonology and doesn't allow guns inside the gates; and The Reverend Wayne's Pearly Gates, which is a nation-corporation based on speaking in tongues.
Within a square mile or so, all of these franchulates may be in business, which allows some helpful services for their citizens. For example, if a citizen of Mr. Lee's Greater Hong Kong is being chased by some armed racists from New South Africa, they could duck into the gates of Greater Hong Kong, where guns are not allowed, and a robotic security force backs up this edict. This is also great for Neal Stephenson throwing in some plot twists.