As far as I'm concerned he just asked a question which can be answered without the need for 'defenders' to show up and challenge the questioner - and with that stifle the discourse here.
"How is this a plane? Is it made of wool?"
"If it was made of wool it would be a comfy hat, it not being made of wool is necessary for it to be a plane. Notice how I'm not even claiming that it's a plane."
The answer is: "social experiment" apps and games are just cash grabs with a veneer of clever marketing to them. The Million Dollar Homepage was probably the first one this blatant though.
The outcome of the "experiment" is known in advance: people will pay unreasonable amounts of money for objectively worthless things if you can convince enough of them that it's cool. If it were an actual experiment, there would be some analysis published after the fact and the money would either be reimbursed or donated.
Social experiments aren't experiments and they're mostly anti-social if anything. In video content it's code for (staged) "prank" (or harassment). In cases like this it's code for "grifting".
Are you accusing the pay per letter scheme of being grifting?
How? They aren't misleading anybody.
How would you differentiate between cash grab and social experiment?