There are few alternatives and it is going to get a lot worse as more people fly and there are no serious plans to expand airport capacity. This is so around the world and the alternative is to slot control the # of flights. As between HKG and GLA, you can imagine which flight drops off.

A lot of this can be ascribed to our fellow passengers. The more buses, the more time it takes to board. If the bus can accommodate 45 and there is a person with a clicker taking a head count, they know that there is space on the bus. The passenger does not.

Ultimately commuter services such as this have become local buses with wings. That won't change.