> Firstly, the merchant still gets the sale and is happy (it's like boasting about getting 20% off at Bed Bath and Beyond).
True, but they would have gotten more money had they held their ground. I was still going to buy the item, sometimes I abandon the cart accidentally because I got distracted.
However if you shove a discount in my face assuming I'm about to walk, I'm going to use it even if I was just about to pay full price without hesitation.
> This is to say: you have not found a loophole; you are not a concern to the merchant; no one should be frightened by this tactic because of your story.
Assuming the 15%-20% is all extra markup, this is true. Also it's not "my story" for the record. Sites like retailmenot index cart abandon strategies. Way more people are going to use that discount than just those you intend. If that's an acceptable loss, then great.
It's still not necessarily a great idea depending on your business.