I think you're leaving out a very important aspect of graduate school, which is simply the ability to experiment and find out what you truly love to do. You can be pigeonholed into a business you don't particularly like, just like you can with a graduate project. But I feel like graduate school offers you much more flexibility and time to figure your shit out, at which point by the end you atleast have a solid credential to back up your work ethic.
I am a new grad student after spending a few years in industry. My advice for people who don't know what they want to do is to go straight to work. Don't go to grad school. It is much nicer to figure out what you want to do while earning $60k+ than $18k.
I don't feel like money is the issue though. When you're working for a company your job is to produce something for them--something that moves the company forward. In grad school, your work is much more selfish. You have ample time to think about problems in ways that only you can solve.
