If anything, this is healthier for people's personal information. Companies seeking such a service typically resort to purchasing homeowner information in bulk

If anything, this is healthier for people's personal information. Companies seeking such a service typically resort to purchasing homeowner information in bulk from other services. With such a USPS service, it decreases the demand for such databases, and with it the incentive to create such databases. It is unlikely that the USPS will overwhelm homeowners. Presumably the USPS will limit received promotions to one per day. That can potentially give the USPS an additional $60/year in revenue per household, at marginal cost.