The technology knows that you were in the market for a toilet seat so it’s serving you up ads for a product you’ve demonstrated interest in. It doesn’t know that you’ve already bought a seat, however, which is why you’ll continue to receive those ads in the short term. As it then continues to follow your online journey it will see that you’re no longer looking for toilet seats and will update its algorithm to stop showing you these targeted ads. But, until we give up access to our banking / purchase data, it won’t be an instantaneous switch. So, in your case, the ads aren’t ‘working’ / useful, but there will be many other people who are in the market for toilet seats and haven’t yet bought one. It’s a numbers game

In Peter’s case, TV ads are usually managed by media buyers who will use demographic information to target ads to the typical viewer for whatever program is being watched. However, sometimes the slots don’t fully sell (especially on niche channels) and so the agency will occasionally throw the ad buyer ‘bonus’ slots that are more tangential to their likely interests. For Peter, they may look at golf in the summer and think ‘Kids are off school, possible they’re watching golf with grandpa’ (my kids actually do this a lot!) and so figure that bonusing ads to this demo is no cost to the advertiser but serves a potential indirect audience and benefit to the buyer. Again, it’s not working in Peter’s case, but when my two are watching golf with Grampy it definitely serves a purpose!