Not accepting gratitude may be a Chinese virtue; but it is a heinous crime before the Holy Creator.
For that is pride at its ugliest.
Jesus said in Luke 14:14, that one is blessed to give to those who cannot repay. He did not say give to others who can appreciate but refuse their gratuity. This is not the way to seek the Kingdom reward. Christ was calling for a giving to those who has no reason to appreciate.
The proud listens not to this teaching, but merely twists it. Therefore, they want others to need them. They need others to need them. And by refusing payment (refusing payment is not the same as revoking/forgiving payment), they feel they have maintained their "compassionate" status. Such selfish pride, should not be present in any Christian.
Should they think they are "that" compassionate, then let's see how they treat strangers and the homeless.