I've never had a problem spending the night in an airport. AS long as you stay airside you're good. Once I left MIA to go sleep on S. beach overnight so I could see the sun rise but the bus driver strongly discouraged it as she said there numerous bums and it wouldn't be safe.

Im referring to an air mattress the size of an aerobed. Different brand but same style, not a self inflating pad. I don't see what the problem would be as it fits in my carry on and we would be out of the way. We're continuing onto an international destination so I don't be want to bring it if anyone has experience of them not letting people. And I know it sounds redneck which I'm fine with. Air mattresses make great rafts to float down the river just in case you've never tried it.