Key takeaway: "Private searches are acceptable, but the introduction of cash payments, as well as the FBI having an official liaison with Best Buy suggests the searches aren't really "private." Instead, the FBI appears to be using private searches to route around warrant requirements."
The FBI is paying Geek Squad members for discoveries, not as direct employees. This has two awful impacts. First, it incentivizes searching every single computer touched, rather than just reacting to suspicions or FBI requests. Second, the 'commission' nature of the payments is being used to argue that these are "private searches" exempt from warrant requirements, which are only connected to the FBI after the fact (despite what is apparently a standing expectation of commission).