Actually, the images are stored off-line at some sort of hosting facility, so, it doesn't really effect J-Ref's storage space, (unlike uploaded images), but nonetheless you bring up a very good point about bandwidth...
The more images and text that J-Ref has to serve, the more it costs the operators of the site... And of course, we are lucky, this is a free server, but at the end of the day, someone has to pay the bills.
The least we can do is to follow the rules, and keep the prices down for the operators.