Cloning

No, the only reason I can imagine is for breeding purposes.

Look for yourself. W4-6 growdiaries.com/diaries/242323-apricot-auto-lemon-cherry-cookies-auto-purple-lemonade-auto-californian-snow-auto-gorilla-cookies-auto-grow-journal-by-trutratri/week/1410155

Highly subjective question. If you grow autoflowers and want the same exact crop, then yes. If so, your SOP should likely include taking a cutting early no matter what.