Oh I'm sure that's true. On the other hand, at the MRO I work for we have very specifically removed plane cleaning from our contract. We don't do it. And further, whether the plane gets a wipe down between flights depends entirely on the turn around (I'm friends with several flight attendants from multiple airlines). That nightly thing sounds nice but tell me, how many planes have down time overnight?

We used to have a contract to do deep cleaning of everything. There's anywhere from 6 inches to a foot of dust behind every panel I have ever removed on a plane. We gut aircraft regularly for maintenance covered in all manner of things. Sticky floors, sticky and or dirty windows and wall panels, lavatories where it is clear there have been multiple spills that have not been properly cleaned, just wiped up between flights. Galleys where drinks or coffee have been spilled repeatedly. You can say false if you'd like but I am well aware of the standard of cleaning on Southwest, Frontier, Jet Blue, American, Alaska, and Virgin Atalantic planes.