Over time the people using the sec.8 vouchers will be re- segregated into the towns that are poor. Upper class and middle class towns and neighborhoods are desirable to live in and apartments get rented without the govt. paying for it.
If you were the landlord who would you prefer as a tenant? The individual with good credit, good job and an interest in maintaining both, or the individual (usually single mom with a couple kids) with no job, no credit and no history of taking care of other peoples property.
Slumlords who don’t want to keep their property up, who might be just holding the property to sell at a later time ... those landlords love Section 8 housing. It give them income with minimum upkeep on their part.
If they wanted to take care of the property, they could get higher rents.