Regarding the last point, at the very least SIAI would be better off not advertising that several projects are partially funded to the tune of $5 out of thousands. It doesn’t exactly motivate one to open up his own wallet for a similar small donation.
If you need to keep contributors updated on the extent to which their projects have received funding, perhaps do so privately by email on request?
It seems like most situations that this theory covers are already explained by either: (a) people seek status not only in the context of society at large but also in the context of small groups (b) for the cases where no one else knows, ego—people seek to feel good about themselves (including that they are smart)
Perhaps the (b) cases are explained better by the “seeking plausible belief in own status” model, but I’m not sure that that’s clear, at least from what’s been written so far.