A job can be just a means to an end, and there is nothing wrong with that. Trying to get your employees emotionally invested is just a way to increase productivity while keeping labor costs down.

I worked in advertising for over a decade, so I can definitely agree with some jobs being a means to an end, but I disagree about the purpose of getting employees emotionally invested. In my experience people that are emotionally invested do better work than people that don't give a shit about anything more than a paycheck. They suggest improvements and argue with coworkers about how features should work because they understand the product and care that it succeeds.

When did being in your products' target market become a precondition to being good at your job?

That may be a valid argument for many jobs, but I can't imagine who isn't part of PayPal's target demographic.