OKAY! I think I figured it out! Try this:
Upload your own image, then select a popular image and choose to add an image. The option where you place your image INSIDE the popular image and use the sizeing thingy to stretch your image to cover the popular image. them caption and post in comments. Go back and delete your image from your templates. Your image should still be in comments, but not cluttering your own personal templates. I just tried this and it worked.