Why do all pics in emails stay on att. @ photos until deleted from Email

I don't want all the attachments saved , but would like to keep the emails. I find these in my classic mail

Why do all pics in emails stay on att. @ photos until deleted from Email
the attachements are tagged to the email.. its not possible to just keep the mail and delete the attachment.. you either have to save the page in your system..or





forward the mail to your mailid self and delete the attachement while doing so.. then the mail will be there but the attachment will be gone..then delete the original mail.