Outside items (like furniture) are subject to expanding and contracting as well as anything subject to moisture or mildew/mold. 

@Sriram Kumar Bikkina My guess is that your friend may be trying to bring awareness to the fact that crawlspaces can typically create alot of problems particularly moisture intrusion, dampness, mold, etc. and can lead to moisture damage to framing components.

not sure if i mentioned this one... a few months ago the tenant called and said there is some moisture/water dripping from the kitchen cabinet under the sink.i went there and saw the entire inside of the cabinet is wet. it's been dripping for some time. i asked her why she did not call me earlier and she said, "I never use this cabinet". when i looked around, half of the kitchen cabinets were empty.

I smelled bs and I did it anyway and we found mold in the basement ceiling rafters, caused by bad gutters allowing moisture into the basement.

You definitely don't want  moisture in there, otherwise you're looking at all new roof decking eventually as you mentioned.

With that you only need to lay down a vapor barrier, though most of the floors I have installed said they only need a vapor barrier if the results of the moisture test are over a certain threshold.

I have my home inspection and termite/moisture inspection tomorrow afternoon and will be getting the official mortgage documents in order as soon as the inspections both satisfy me.I will be getting a conventional bank mortgage at 5.25% with 20% down and 2 points.

How did you address the underlying problems of excess moisture in the crawlspace?

Moisture and laminate do not do well together.