Shill
noun
One who poses as a satisfied customer or an enthusiastic gambler to dupe bystanders into participating in a swindle.
intransitive verb
To act as a shill.
To act as a shill for (a deceitful enterprise).
To lure (a person) into a swindle.
Yup nothing good or bad here... just 'marketing'... no negative connotations at all.
Shilling outside of marketing is bad. Shilling within the context of marketing is neutral.
Calling people "marks" when they should be clients or customers-- that's bad.
I think you're missing the point and adding your own definitions. Shilling has always had a negative connotation. People can endorse a product without shilling. It just requires an honest opinion and transparency. These types of 'marketing' efforts are often legally considered fraud and there has been government intervention in extreme cases. That being said I like the core of the idea, I would just like the language cleaned up for good optics and better results.