If it's good for transit to have information available, then why do we have information black holes like in Northern New Jersey? Competing priorities, that's why. Maybe some complacency, too.
The City of New York is interested in development of the City. It recognizes that suburban commuters contribute to that development, but until recently has seen its role primarily as a facilitator of car commutes through its free bridges. Only recently has anyone in city government shown an awareness of the value of getting those suburbanites to take transit.
The State of New York is interested in the economic development of the State. Its agencies, including the MTA, have no incentive to make it easier for people to go to New Jersey. The MTA also runs subways and buses, and sees private bus lines as competition for its services.
New Jersey Transit sees part of its mission as getting commuters to Manhattan, but has no interest in anything that doesn't cross the river. It runs trains and buses, and is barred by law from destructive competition against private operators, but it doesn't want to give them free publicity, either.
The Port Authority is concerned with movement across the Hudson and economic development on both sides, but doesn't care about anything that happens too far from the river, except for the airports it runs. It produces maps for its PATH train service, but not for other organizations.
Small operators don't have the time or money to produce and distribute information about other services, but if they did, what would they get out of it?
It's a bit more of a mystery why medium-sized consolidated operators like Coachusa don't bother even printing a map of their routes on their websites. Of course, as commenter Busplanner points out, transit mapmaking "is a very slow and costly process."
Mapmaking certainly was a very slow and costly process, and I think a lot of transit operators are still thinking along those lines. But I don't think that's true any more, in this age of global positioning systems, geographic information systems and Google Transit.
Take your average college graduate and give them a one-month course in GIS. In another month, they could put out a very good county bus map, or a decent draft of a statewide map. Probably a lot less than a month, right? I don't know, but it seems likely to me.
Other reasons I can imagine are inertia and impatience. Coachusa is making millions off of its service. It's cheaper and faster than driving, so people keep taking it. It's pretty close to a guaranteed monopoly, so why bother putting in a lot of effort to get more? There's also no immediate reward for producing a map or any other kind of information product. You may get a bunch more single trips, and a number of investments, but it takes time for those to translate into habits. The value is not obvious, so it is often overlooked.
I'll talk about some possible solutions in a future post.