The only problem with not quoting a post....
Sometimes if a thread is busy and you're writing a long response to the last post, you'll submit your post only to find out one or two people already jumped ahead of you. Then, without the quote, it can be unclear to whom you are responding. It has happened to me multiple times (probably because I type too darn much
However, I'm totally supportive of editing an image out of a quote. Unless your comments are specifically regarding the picture, you really don't need to quote an image.