ps. why not include md5 on the download page?
This question has an inherent assumption that there is a reason they're not there. I would surmise that no such reason exists. ;)
That page isn't exactly generated or anything. It's just a plain old static page, mostly. We'd probably need to write some more code to have it always have the proper links and such, and presumably nobody has bothered with it much.
There's no reason it can't have those, since we do have them on the release-archive page, but hashes aren't exactly user friendly and there's not really any need to confuse people with them. And if you think that nobody would be confused by a link that is largely irrelevant to their particular purpose, you should see some of the emails I get...
ps. Sizes on the download page are fixed.