If you go on YouTube and put "Sonic" in the search, at least one of these kinds of videos will show up in the first five results.
I think whoever makes them hopes children will watch them out of naivety. A 6-12 could be like, "Oh boy! A Sonic cartoon! Wait... why is that little Sonic playing in traffic?"
No, really. I never found those videos and I do searched Sonic once everyday to check if there is a new video that I could post in this forum.
Most of them that showed up are latest Sonic game's gameplay videos and official trailers. I only check the top 10 though, never bother scrolling more.
Was my search column tailored to my watch history? I don't know, one for sure is I never tinkered anything in the setting.