Ahhh, know i got it.
I do not think like this.
If i "give away" money, it is to pay/honor things that have already been done.
No further obligations attached.
Else i make contracts or hire and obviously take responsebility in development process of a person or a project.
The world could be so easy...
Thx for the hint @marxian

Edit. Waaait a minute. Is this why Flattr and Patrone are not working? Creators don't use it because they feel pressured by the ones that actually only want to say thank you??