Costco will let you return the device for up to 90 days but you can only exchange it within 14 days. Who needs 90 days to tell if a device is the one you want or not?

The problem isn't with commissioned sales reps. The problem is that after 15+ years of buying these devices and services, people are still claiming ignorance instead of educating themselves. It doesn't matter where you buy the phone, if you aren't educated about your purchase options and don't take the time to get educated there is nobody else to blame.