Also without naming usernames...
I've definitely seen this. This includes a handful of threads discussing legitimate concerns about BULLRUN-style influence that were suddenly insta-flagged, punted from the front page and hidden form the main index[1] by those same shills. Several times the "nothing to see here" explanation took the form of a sudden concern for "not wanting to tarnish someone's reputation".
[1] which means moderator access
edit:
Anybody that thinks this is unlikely needs to watch PHK's "Operation Orchestra":
https://archive.fosdem.org/2014/schedule/event/nsa_operation...
But a good proportion of prior threads on the topics of NSA surveillance, silk road (or tor in general), CISA, FBI/prosecutorial overreach, etc - has certain somebodies reliably pull the Frank Drebben "nothing to see here" routine regarding abuses of authority.
The shilling that gets upvoted is rarely overt. It's almost always of the "this isn't so bad, citizen, carry on" or "criminals deserve it" variety that dramatically understates or deflects the threat posed to us by authority.