Not to leave wheels turned out after parallel parking. Bloke here did that and his car was scraped by a drunk driver.
With no out turned wheel it would have scratches and a wing mirror. With the out turned wheel taking full impact, a write off.
On an 'ill, I was taught that you should do so, such that handbrake failure would have the car roll into the kerb
Legal requirement to do so in certain parts of the US I believe (SF?) - you can be ticketed if the wheels are seen to be straight.
(Historic cause for consternation among owners of Citroen CXen, I believe, where the Diravi power steering would straighten the wheels up without you asking.)