Seatings and standees

An upmarket Chinese restaurant near to my flat has a sign outside saying "15 more seatings downstairs". Why is it that I like the word 'seatings' but detest the word 'standees', which is becoming increasingly common in a public transport context?

Incidentally, 'seatings' doesn't make it into the OED, but 'standees' does - albeit as "chiefly North American".