Licenses of artworks or stock photos often state that they are free for non-commercial use.
Assume I create a poster for an event. I do not sell the poster, but the event is commercial (has an entry fee. or sells drinks. or something like that). Am I then allowed to use that stock photo?
For example, pexels states
All photos on Pexels can be used for free for commercial and noncommercial use.
Attribution is not required.
Giving credit to the photographer or Pexels is not necessary but always appreciated.
You can modify the photos. Be creative and edit the photos as you like.
I am interested in an internationally accepted answer, if there is one. Otherwise, I am interested in US, European Union, and Swiss law.
Related questions, but without any sources (and so seem like the answers could just as well be somebody's opinion):