not needed. unless you come off the racetrack and you urgently need a loo for whatever reason then no, you dont need them really. also agree, they can caus big problems too, and not worth the hassle. just take it handy for the last 2 miles and your fine. i certainly never left a car idle 60 second after fetching milk and i've NEVER blown a turbo/engine. if i did give it socks i took it handy the last miles or so, and let it idle till i fetched my phone/wallet/closed windows etc and by then its fine to switch off.
the guys that go to the shops and let their car idle for 2 min afterwards make me laugh.....