That issue in itself might be worth a thread

. There are many LL owners who don't allow big pics on html pages to prevent submitters from abusing surfers with banner farms, trojans, etc. I allow big pics on html pages so long as there's only one sponsor link/banner and it isn't obnoxious.
In the end it's a balance between a good surfing experience for the surfer and a money making opportunity for the LL owner. You may find that many LL owners who don't allow full sized pics on html pages for submitted sites may be willing to bend the rules on HFS. Then again I could be wrong.
Personal opinion: as long as the ads are tasteful I don't have any issue with them.
My biggest personal issue with HFS is the shameful reuse of templates. You'll find plenty on that in the other threads DD linked to.