Yeah, some bands are out of their minds with the openers. We had one concert where they really wore us down with them. By the time the headliner came out, it was almost 3 hours late and we didn't stay for the whole show. Honestly, I'll probably never be on time for a show again after that experience. They should have a concert start time and a headliner start time so people can plan according of when they want to come.
I would love that. I actually went to a concern for the opening band and only stayed for the headliner because my date liked them. I would love it if I could get reduced tickets to only see the opener, or be able to sell the rest of my ticket to someone waiting for the headliner.
It wouldn't be everyone but even if it was, so what? If no one is interested in seeing an opening band it doesn't mean they should fuck with the schedule so they can make people watch them anyways just so they can get famous.
Not that I go to concerts at all anymore anyways because fuck the live nation/ticket master monopoly.