It is a detail that tells the reader more about Mexican culture.
The author likely includes information about the person mopping the floor to emphasize the theme of working class individuals in service roles often being overlooked or underappreciated. This detail may also serve to underscore the mundane and routine nature of the airport environment.
to emphasize a dangerous situation
smd
If someone refuses to take their shoes off in an airport, it is likely that they could be in serious trouble. They will not likely be allowed to get on a plane, and they may be kicked out of the airport, or even arrested.
To emphasize a dangerous situation. -Apex
Dallas
Most likely, 'schedule'.
Most likely called "the Orlando Airport Shuttle" - they can be quite subtle sometimes.
most likely Cairo airport
More than likely, you are near an airport. That is a beacon.
Most likely from moisture. If you are mopping the floor, steam cleaning it, or using any kind of water (even a little) it can swell the joints. It also could be from moisture in a cement slab if its on one.
Most likely at a major airport or at some banks.
Most likely because of the Wind and it's speeds