Good points. I'm not letting the lazy thinkers off the hook, but I think that what many people are seeking is validation. They've largely made up their mind and are now running interference against cognitive dissonance (i.e. buyers remorse). In other words, all they need or want is someone to tell them they are making a good choice, and they're off the races.
Interestingly, the validation doesn't even need to be specific (i.e. "the Megatron Kilobuck images better than a solo pianist at Carnegie Hall."). Rather, "You won't be disappointed," or "I have this model as well and it's fantastic" are the statements the buyer has yet to hear. Of course, there's that "objectivity" (as if ANY of us on this or any other forum are actually capable of being objective about our gear. . .it's OUR GEAR!
As a salesperson and sales trainer, it's a powerful bit of psychology to know about. Now, I expect to get flamed for that statement (bring on all the "smarmy salesperson" comments). But I respectfully disagree with the general notion that sales people end up taking advantage of, and foisting product upon the unwitting public. . .that's another thread completely and I'm happy to contribute a POV.
In reality, the buyer has probably conducted significant due diligence prior to getting to the point where they are asking for validation. Assuming that's the case, they've often qualified their choice across the objective criteria (price, build quality, environmental/system suitability). Now they just need to hear that they're right via that last bit of subjective validation.
On the other hand, some people are just lazy and want others to think for them. . .enter Sales Vulture (i mean sales person)!