Advertising has become 'active', very recently in the overall lifespan of advertising. For most of it's lifespan it was passive, it blared out at you from the TV or radio or bus stop. Now, however, it's reaching out and taking pieces of you back for analysis and reconstruction, and on-selling to any other entity interested in doing the same.
The reason is greed, yes.
We can't regulate human greed, but we can regulate the manifestation of its symptoms.
We can also choose not to work towards expanding the capacity of said symptoms.