[somat]

On the other hand I can imagine there being some sort of study that claims that having to "check the warehouse" makes the client now invested in the process and more likely to complete the sale.

I get it, sales and marketing are an essential part of doing business, you will not have a business if you can't sell anything. But it is an inherently evil practice, the whole goal is to coerce somebody into doing something they would not have other wise done. When kept to a moderate amount this is not a problem, the business sells things the customer gets things, everybody is happy. But sometime the marketing department can push thing to a very unhealthy level, psychological manipulation, dark patterns, obsessive tracking, etc.