> How does watching an ad decrease the amount of money I have?
There are at least 5 parties here:
· Content producer (spending time and effort making original content that people watch)
· Platform
· Advertiser
· Content consumers
· Thief
In your comment you're Content producer. The advertiser pays the platform who pays the content producer, and the amount they get is based on the number of views (there are other factors, but I think views is the main one). Let's say they're getting X views per day. Then the theif takes the content and uploads it to their own account with ads enabled, and gets Y views per day, and gets paid for that. No one is going to watch the content on the producer's channel a 2nd time just to make up their view stats, so now the producer is only getting X-Y views per day and hence is paid less.
This is the reason Youtube's Content-ID exists.
The illegal act here would be re-uploading the video. I'm asking how downloading the video by itself increases the amount of money I have.
It doesn't, and I never said it does. You asked for an explanation of how ad revenue theft happens, and I gave that.