It's starting to be pretty clear this trip to the airport is going to be the ending arc of the whole manga. There's only a handful of pages left, after all.
If somebody told yuki the manager would pick mayu up from the airport, she could have gone with him and they would have more time together. They could have had a nice long ride on the train and maybe there would have been time for a date in tokyo. Would have been nicer and more romantic I think. This car ride is just an excuse to include the cast once more it's honestly so cliched it's kind of painful
After reading the next chapters
now I know the car ride was completely meaningless