This is just the pros having more tact than amateurs, and actual writers. I do see some “influencers” that do more of a pure product placement. They just happen to be drinking a specific energy drink in every video where it sits perfectly with the label out. I see some YouTubers trying to get better at integrating the ad into the video, but most of them can’t be bothered to write and record a custom script.
That said, Subway often seemed to get pretty heavy with its product placement. The last season of Chuck had a good amount of this, even what was essentially an ad read right in the middle of an episode by Big Mike. On Community they personified Subway and based a whole episode on him. In the Office they brought in Ryan Howard to say “eat fresh” over and over again, and even called out that it was for Subway to make sure it didn’t go over anyone’s head. Subway was big on sponsoring the last seasons of struggling shows with loyal fanbases, and littering the episodes with Subway product placement to the point where it became a plot point. I remember Zachary Levi (Chuck) tweeting out to ask everyone to go buy some Subway before the finale. It sounded like if Subway saw enough of a spike in buying from the sponsorship, they might fund yet another season.