I have a tip too.
You do not need to tip the girls, save your money for more important purposes.
A lot of them may earn more money than some of their customers.
Once they return to China, they will also likely delete your wechat etc, and all that $$$ will be spent in vain
If you feel you have a lot of $$$ to throw, you can tip those poor elderly pump attendants who earn about $1500 per month:
https://www.channelnewsasia.com/news...amily-10090746
They are in greater need of your kindness and generosity.
However, if you still feel that you wish to be a carrot or a robert, it's your freedom of choice as well.
I usually will still tip my regulars during CNY period with some ang pow.
Wish everyone happy cheonging. Huat ah!