I remember seeing this at an airport once before. They didn't have this at my local international airport so I thought it was some crazy thing for paranoid fliers. But in hindsight it has a purpose.
The companies that provide these services claim a lot, but it is definitely going to provide the protection from the following things:
- Tampering (or at least make it clearly evident)
- Unauthorized items
- Accidental openings
- Weather (rain, snow, etc)
The companies go on to suggest that you can also prevent scratches, wear and tear, and other such things. I find it hard to believe a thin layer of plastic could do that, but it probably does provide some degree of protection from those too.
The most convincing however, is the protection from Weather. The tarmac where the plane is loaded isn't protected from these things. If I have fabric luggage, I can use these wrapping services to prevent rain, mud, or frozen winter gunk from getting into or on my luggage. Possibly damaging it permanently.
An interesting note. When they wrap the luggage, they often times cut out the wheels, if a pull/push/rolling set, and also some of the handles, so even though it is wrapped up you can still use it like you had.
Also the device they use, for anyone who hasn't seen this, is an interesting combination of a kiosk and warehouse skid wrapping machine.