Yeah I only own a credit card because it's basically required. I hate the whole system and find it stupid but "that's just the way the world works." The only positive of using it is my 1% cashback, so I "earn" money by paying bills.
Not really. Credit cards are a secure but unreliable form of payment - far safer than carrying cash but for a number of reasons can end up not being accepted for a perfectly valid transaction. At that point you need another or things can get annoying.