Late post but in case it is still helpful for someone
I always politely let the hotel know if it's my birthday (or a birthday of someone I'm travelling with) prior to arrival, making a request for 'anything they can do to make my stay a bit more special.'
For my latest birthday holiday in Seoul and Shanghai I received:
- Birthday fruit platter from the
Ibis Styles Seoul Myeongdong
- Birthday gift of tote bag, calendar and toiletries from T
he Alcove Hotel (Seoul)
- Full-size birthday cake and birthday card from the
Sofitel Shanghai Hyland
From previous stays at other (not always Accor) hotels, we've received chocolates, desserts, birthday cakes, upgrades, bottle of wine.
I always say it's worth asking!