1. They absolutely do design it for the intended users: themselves. It just isn’t you. They’re scratching their own itch, not your’s.
2. The OP opinion conflates free/paid with closed/open source. Paid software can still be open source, and so beholden to the paying customers. Free software can be closed source.
3. The objection is really someone who isn’t contributing anything complaining that people giving away something for free aren’t acting like they owe them something.

This is a Choosy Begger situation. Want someone to work for you? Pay them. It has nothing to do with whether the software is open source, but whether it’s free or paid.