Spitoon...
In many parts of the world, airports and ATC are becoming more commercialised and this usually means that each user pays for what they use. If you think about it, providing an airport or an ATC service costs a huge amount of money and someone has to pay for it all. In some places these services were viewed as part of the transport infrastructure provided by the State and paid for out of general tax income. As things become more commercialised the aircraft operator generally gets billed for the services that they use.
...unless of course you're M.O'L and Ryanair in which case the airport / local authority / regional authority pays you...
pp