FWIW, nobody here missed that. That discussion has been had, and beaten to a bloody pulp, many times. But again, this goes back to my first comment. You only have 3 FP+ per day, and while that does save some time, your far from having an entire day of "no waiting in lines". The FP+ selections usually fall into a certain part of the day, (morning, afternoon, or evening), so if you use your FP+ selections in the morning, the rest of your day is straight up old school waiting in line, and yes, even in line at kiosk to obtain additional FP+.
I dont think "park behavior" is any different. You make it seem as if every park guest automatically goes to a gift shop or ice cream stand while "waiting" for their FP+ window. Most are cramming in more attractions. People loved Mickey Ice cream bars before FP+ and they arent going to buy more than normal simply because they are waiting for their FP+ window. How was legacy FP any different? You still had to wait for your return time. Did people not know the shops and ice cream stands existed back then while they were waiting for their return window, the same way they wait for their FP+ window now? And the fact that Disney hasnt added much in terms of UNIQUE merchandise to the shops that people are supposedly "waiting in" doesnt give the guest much of a selection to browse through. Most of the shops sell the exact same thing, so after day one of a trip, youve already seen most of the merch available. There will always be parents who will buy their kid that plush mickey doll or that Elsa dress. That was going to happen regardless, it did not happen because of FP+.