Most of these sinkholes are caused by burst or faulty water mains

Would not doubt it.
Wonder if this is why homes explode also?
We can see by glancing around, nothing is being built to speak of, no new apartments, no gas lines, phone lines, just cheap labor who bust gas lines every time they dig. Freeway repair broke within 6 months and fell on cars. Second-world ahead.

Would not doubt it... except for the fact that at a certain point, everyone calls in and says "Where the fuck is my water"...

I do not believe this to be the case.

Water mains, and in my experience storm sewers even moreso. Repair of basic infrastructure is not on the federal and state radar - unless there is an HOV lane, Bike lane, or widened sidewalk in the project, no dollars will be forthcoming... and here we are, sitting upon trillions of dollars of these much needed basic necessities at or past end-of-life.

clarification: Not saying that this Bush family one wasn't natural - just saying that every type of earth failure I have ever dealt with has been due to civil infrastructure failure.

Op, you are correct sinkholes in places not known for an underlying limestone bed tend to be caused by outdated and failing water and sewage systems except in areas with underground water systems such as Tibbetts brook in the Bronx that sometimes open up naturally existing underground caverns due to natural water erosion.

However, your correlation to spending money on “corporate buddies and methadone programs” is a bit over the top as New York City is a plethora of undocumented or forgotten schematics within a vast city of deep underground structures.

Sinkholes

Human-induced sinkholes are consequences of land-use practices, especially water pumping and construction. Other types of human-induced sinkholes result from abandoned septic tanks. Even as communities modernize and switch from septic to sewer systems, the old septic tanks may remain in place. The concrete cover may eventually crack and break down, allowing the earth above to drop suddenly, especially beneath the weight of a person. In one week in 2004, two such incidents occurred in New Jersey and in Texas, claiming the lives of a 2-year-old girl and a 92-year-old woman. Check with the local zoning office, which should know whether the house was built before sewer lines came into the neighborhood, which would indicate the possible presence of an abandoned septic tank; decaying, buried organic material, such as tree roots or trash. In 1993, a 7-year-old New Jersey boy fell to his death in his front yard after the ground beneath him gave way. A vein of tree debris, which had been dumped there many years before, had formed air pockets into which the soil gradually seeped, leaving a weakened surface that appeared solid; collapsed mines; over-pumping existing water supply wells, or drilling additional wells in close proximity, thereby lowering the aquifer; and the period following housing development, which adds pressure to the supporting earth.

[link to activerain.com]

mini blackholes.