Here in Columbus, the city sends out maintenance crews on nuisance properties with high weeds, etc..  The homeowner gets the bill, and if it is not paid, the maintenance costs get tacked on to property taxes.  For the neighbors, it's not as good as having someone occupy the home and keep up maintenance, obviously-- the city won't come out until there's already a problem.

If the situation were always like it is in the pictures accompanying the article, with the law-abiding friendly tenants neatly manicuring their lawn, then of course this temporary fix would be a net good thing.  However, I doubt that this situation is typical, and may not even be typical of this would-be adverse possessor's 20 properties.  Someone who moves in under this kind of arrangement is going to probably assume that their tenancy is not a long term arrangement, so they aren't going to have much invested in the future of the property or the neighborhood.  If a gang of drug dealers moves in, neighbors might not be so happy.   Meanwhile, even if you are lucky enough not to have a drug dealer move into the vacant property next door, the boost in the level of maintenance may be fleeting.  If and when it becomes clear to the architecht of the scheme that he is not going to get to keep the property, he will likely abandon all attempts to maintain the property, or assure that his tenants are doing so, or he may just be in it for a few months rent from the very start, never intending to continue maintenance from the start.