Recall that EXIF data is textual, and therefore no larger than kilobytes in contrast to the megabytes that JPEGs otherwise take up. While this may eventually add up to gigabytes of bandwidth, it will only be after downloading terabytes of JPEGs.
One can imagine a variety of small things that are only useful to a minority of visitors, and go unnoticed by the rest. "alt" attributes on images are one example, that are often used by the blind, but are mostly unused by anyone else. Do you think provisions for the blind should be removed, due to wasting (tiny amounts of) data?