To some extent I am in two minds about this one. I'm not sure that you should automatically assume that the $250 per night is cumulative, unless stated otherwise.

(Using a more oblique example, if your rate included free breakfast and you didn't take it on Day 1, you would not automatically assume that you could invite a friend from another hotel to have breakfast with you on Day 2, and not pay for it. Similarly, if I had a $100 lunch credit, I would not automatically expect to be able to use it across two different days unless told otherwise.)

I am also not sure why the lack of cumulative credits was such a big deal (except that I assume you were planning to use some of it on your 'free' day which had no $250 credit). At worst, it would mean a bit of rescheduling - ie instead of doing the spa and on-property dinner on Day 2, you would do the spa on Day 2 and eat on-property on Day 3.

None of the above excuses the attitude of the staff, however .....