i had three dozen heavy robes at the inn in maine. from cypress. spa quality, heavy like bathtowels.
yes, three dozen.
started with 20 (maximum occupancy) and then got more because of laundering.
it was expensive but so worth it. this was in 2005, and i got a price break for buying volume.
i loved those bathrobes, with name of the inn on them in royal blue on the pocket. guests loved them, walked around in them, girflriends weekends they would snuggle in the library in them, came to breakfast in them. wedding guests all getting ready, doing each other's hair, would be all around the place in them.
when one got badly stained with hair dye or something, it became mine.
but i would never buy heavy robes again. they took ages to dry. i do mean ages. and you have to wash them between guests. so 3 max in a large capacity washer is a lot of laundry.
go with the thinner robes.
and absolutely get the biggest sizes you can. my daughter is a zero (insane sizing) and she can just wrap a big robe tiightly arounder herself and tie it. but a 4x lady is embarrassed and uncomfortable in a robe she cannot close..