I run a retargeting company and this annoys me too! The reason this stuff happens is because many players in the space soak up advertiser spend by not immediat

I run a retargeting company and this annoys me too! The reason this stuff happens is because many players in the space soak up advertiser spend by not immediately opting users out of product retargeting campaigns after a purchase is made. The advertisers don't always know to ask for this and the retargeting companies make more money if they don't suggest it. These personalized campaigns are so profitable for the advertisers that they don't notice the extra spend being bled out on people who they shouldn't be retargeting. This tends to happen among the big "enterprise" retargeting companies that serve large online retailers like Macy's. There's so many people involved in the deals and operations of the campaigns that no one person is there to say, hey, let's make sure this doesn't happen. The takeaway: Only work with retargeting vendors that give you control and visibility into who you're targeting and why! We do this, but so do others. Not everyone is this lame.