Or to look at it another way, they're perfectly happy to let you stand in a queue, outside, on the runway, in the cold/heat, waiting for them to unload/load the plane that has just landed and is often already late.
(In fairness, they don't _always_ do this at Brussels airport, sometimes using a normal jet bridge).
Decided to head down and work out why, only to get shouted at by a very angry staff member as they wanted to depart early....