What? There's no overlap between Crassus' strategy and the VFD's strategy as described above. The VFD asked you to pay recurring fees just in case your house ever caught fire, and when someone decided that was unlikely, they made it more likely by setting fire to his house.
Note that in this strategy, if someone's house catches fire, that's bad for the fire department, and on top of that it looks like they just committed a crime. The fire department is in the business of threatening people until they pay for a service that the fire department hopes it will never need to provide.
Crassus' strategy is completely different; he operates an actual fire department whose services are not available to other people. If your house catches fire, he'll buy it from you.
Theoretically, Crassus could benefit from arson too, but he really doesn't need it.
Crassus is in the business of buying things that have very little value to the seller (who has no way of extinguishing fires) but have a much higher value to him (because he does have a way of extinguishing fires). Unsurprisingly, this is very profitable for Crassus. But what's the similarity?