You have to experience trying to actually get something accomplished to truly understand how incredibly unintuitive everything from names to button placements to object movement to component selection etc truly is. I've used a lot of different 3D programs in a lot of different domains and nothing comes close to blender. It almost seems to go out of its way to make the most basic excersize a puzzle for the user.
The money for commercial programs is completely necessary in a professional context, since time is money and people have expectations.
But with the 2.8 RC news on HN last week I recently tried it again and I have to say that now it seems like the UI is pretty decent. Left click select, a move tool that works like every other move tool in paint, a clear hierarchy view with obvious nestable layers - it seems like many of the weird things I remember (like "drag the divider between the viewport and the menu bar down to see a secret option pane") are gone or redesigned now.
Check out https://www.youtube.com/watch?v=jBqYTgaFDxU for some example usage or https://www.youtube.com/watch?v=lPVpg4_POww for a preview of the UI/UX changes.