I could pretty much tell you what people at DHS "will" do. They will go straight to TSM and then make a beeline down Sunset Blvd to ToT and RnR. Not hard to figure out. So FP+ allows them, should they choose, to avoid the predictable run to TSM. First, so what? How does heading toward ST insteadof TSM increase profits? It doesn't. How does sleeping in for an extra hour increase profits? It doesn't. OK. So 2% of guests now eat breakfast before heading to the park. Is that the profit-driven, behavioral science that you are looking for? Second, human behavior has changed marginally if at all. Arrive at RD at DHS and observe what happens under this new regime as compared to the old. Watch where people go. Observe how FP+ has socially engineered guests into behaving differently. Know what you will really see at RD? Meet the new boss. Same as the old boss.
It's not that FP+ is reconditioning people to spend more money. It's that some people
would spend more money if given the chance, others would not. So FP+ is designed to enable those that
would spend more,
to spend more. The goal of the system is to make it easier for people to spend money, thus, those with money to spend will do so more freely.
BTW, your assessment of what people will do is off, if you consider me a person.

I have plans to rope drop TSMM / JTA (split up), then head over for a breakfast at 8:30. Then watch a parade, then do Star Tours, Muppetvision, HISTK, and Dis Jr, plus a FP of TSMM. Then catch a dinner at 5pm, then head over to Sunset later in the afternoon, ride TOT via FP, and probly Rockin via Standby, albeit late in the day so hopefully not terrible.
We're a pretty typical resort guest family with young kids. I have me getting on most things I want via FP+ (TSMM, ST, and TOT) and waiting sb for only Rockin, which the big kids can do after mom takes the baby back to the hotel. I think we'll get in the Muppets, DisJr, and other kid-stuff relatively fast cuz it's a SWW Friday (lower kid-crowd, greater teen / adult crowd).
I'm looking at that as a really productive day, doing tons of Star Wars stuff, tons of regular stuff, and all via FP+. Part of the savings here is in that we can avoid travelling down Sunset Blvd most of the day. Under FP-, there would be lots of traversing the park to get tickets. With FP+, I have them in a neat little circle from JTA to Star Tours to TSMM to Dis Jr, ending back at H&V. It really cuts out a ton of waste.
If you think my plan is unrealistic pls share! I am terrified of this day most of all, and want it to go pretty smoothly.