It would be nice if they mentioned something about getting some sort of agreements from the sellers they were aggregating. This just smells of the classic sort of pitfall that the things you are standing on could pull out the rug and leave you with nothing.
Doug from Zinc here. We have agreements with some (but not all) of the retailers that we work with.
Reliability should be a huge concern for any developer choosing what services to build atop. The Zinc API has been operating without a significant service interruption for several years now, and we consider our ability to provide uninterrupted service to be one of our primary competitive advantages.
We have very long term plans for Zinc which is why we've earned the trust of several big institutions. Please reach out if you are thinking of using the Zinc API and would like to discuss reliability.
