The only assumption I can make is that those people who do it as part of a regime have cats who don't mind being crated.
And have those cats said they don't mind being crated...I don't think so. Just like feline declawing is legal in the USA..... to my mind it's cruel as is crating!
Well with respect you can take that as far as you want to - does anyone actually know if cats are happy to have their meals presented to them out of a tin rather than freshly hunted prey?
We can only go by our perceptions of stress, can't we? I
have seen cats crated looking quite content and not the slightest bit distressed so I'm not against it unless the cat is clearly upset and suffering.
But I'm as the same opinion as Den... if a calm, contented cat is happy to curl up for a snooze and stay crated then why bother crating it unless for medical reasons?