I guess using the right-click “open with” option is too hard.
You'd be amazed. I've watched most people mindlessly double-click all sorts of things and expect them to open. The idea of "thinking" before they click is foreign. Doing a right-click-open-with literally doesn't occur to 90% of the users out there. Show them, and they're astonished...
"Wow, okay, that's interesting but why would you do all that, if you can just double-click it?" (Facepalm)