if generous and rich enough to give, then by all means. but IMO, there's no need. I worked in banquet @ hotel thats much higher grade than Orchard Parade Hotel and never receive any angbao from couples. Even when u give angbao, most prob is to be shared among the banquet manager, assistant manager and maybe, the head captain and the permanent staff. However, i do not see any need. They earn a lot also lah.
If u want to give, how much is okay? $100? $200? looks v little also. so might as well keep it.