I don’t know when this started but I noticed it for the first time a few months ago. Some podcasts will have preroll ads that are obviously tailored to me since they are not in the same language as the podcast, instead they are in my native language and if I connect to a VPN in another country the ad will change to one from that country. They also seem to appear regardless of podcast app. I have used both AntennaPod and Spotify. AntennaPod is free so I guess they source their podcasts from some third party website that could be adding in the ads. But since I am paying for Spotify I am expecting not to have to listen to any ads. So who is adding in these ads? Can I get rid of them or am I just stuck with them?
The ads are put in by whoever makes the podcast.
Sure they decide that the ad should exist, but how? When I see a mid-roll ad on YouTube for example it was put there by the person who uploaded the video but the content of the ad is delivered by youtube. Who is delivering the content of these ads?
The podcast company that makes the podcast.
When they make it, they put in an <advertising tag> in the locations during the podcast they want the advertising to be, then they sell the advertising space. If there is no local advert, it skips, if there is one, it pulls and plays that.