I freely spread kindness to everyone I meet.

Offered to a stranger, kindness is sometimes read as a sales pitch. Somebody helps with a suitcase on the stairs and the other person's first reaction is a quick calculation about what is going to be asked for.

That is not cynicism so much as pattern recognition, and it is the small tax on doing any of this in public. You accept being misread occasionally as the price of the other times, when it lands exactly as meant.

The only real defence is to leave straight afterwards. Kindness that does not wait around for a response is the hardest to misinterpret and the easiest to accept.