I've been running w/o remembering to change these items for over 60,000km. Car's not complaining yet. But is it safe to drive vehicle so long with same plugs and filter?!!
Safe? Probably, but bad things could happen. If you've got a plug or two not firing you could be dumping fuel into the cat, which can clog it. If the fuel filter is clogged and starving the engine it could cause a lean condition, which could cause all sorts of trouble if left unchecked.
Tune up your engine, man. Be nice to it so it can be nice to you.