What do you think vibrations propagating through the air are?
Thinsulate is not even close to being one of the most cost-effective acoustic insulations, especially not in applications where having a lot of thermal insulation is also desirable. I won't bother mentioning examples because (based on past experience) I doubt you're really interested in them anyway, because you already believe you "know" what works and what doesn't.
I use USB Clip-on Omnidirectional Condenser Microphones, which cost about $14-$15 each. It really only takes five or six, although more is better.
I guess your next complaint will be that this type of mic isn't "good enough" but in fact, the only real drawback is they are omnidirectional, which is easily changed using the method I mentioned in a previous post. The consistency is excellent because the exact same mic is used in the exact same location & orientation before & after treatment.
As I mentioned before, it always seems to turn into an argument between people like *you* who presume to know what will work best without actually having tested much, if anything, yourself, and those like me who have done that (along with more product research than you would believe). I guess that's the difference between amateur and professional. So, I'll let you get back to your previously established presumptions.