[throw2ih020]

London Gatwick is outside of London, so I assume land costs are low enough that a multi-story car park isn't too expensive.

[0x3f]

Most 'London' airports are outside of London and they still charge a ton for parking. Captive audience. This one is unusually cheap, even for Gatwick.

[Havoc]

I very much doubt this robot is carting them up an incline to a multi story

[7952]

Most of the long term parking is surface rather than multi storey.