Full ack!
IMO the retropie-project and ROMS/Images are two different things - even if they depend on eachother to make sense.
And therefore retropie should never implant any direct channels to any sites or databases containing copyrightet material.
It is no Problem to find enough food for the rom-folders by just searching the internet with Google or any other search-engine.
The retropie-project should stay clean, there is no reason to offer any shortcuts to rom-collections imo.