Well, for main picture cars it is not especially useful, but for the additionnal views it helps, yes, as we can then copy/paste the code (but for additionnal views, you can add them yourself later when main car pictures are uploaded )

Actually it depends who has time to upload pics.
Some admins prefer download a zip from the "contrib" mailbox (like Garco, I think), other prefer copy/paste imageshack URLs (like me), and some do not have choice because they didn't ask me the password for going check the mailbox