Let's keep in mind that propaganda, advertising and public relations are all spouting from one and the same sewer. Hell, PR as a modern profession is a descendant of propaganda[0].
It doesn't matter whether you're selling a product, a service or an agenda. The mechanics are the same, only the labels we assign them differ.
Creating false grassroots support for your product? Astroturfing. Creating false grassroots support for your agenda? Sockpuppeting.
An early episode of Motherboard's otherwise mediocre podcast "CYBER" did an interview with Gruqg.[1] That episode has an incredible amount of material about the nature of propaganda and modern information warfare. It's 40+ minutes, and well worth the time spent.
0: https://en.wikipedia.org/wiki/History_of_public_relations
1: https://www.vice.com/en_us/article/qv7wmv/former-exploit-bro... [warning: stupid consent modal; find the episode in podcast search instead]