That is true, there are many manufacturers that keep up to date and add their own patches. Though for a frontpage, I don't think that is true. It is much easier to update your software, than going through all patches, keeping up to date. So for clients I believe you can maintain 5.3, but for just your own frontpage? I doubt it...

Also I would believe that having PHP 5.3 is an unique selling point, so they would advert that unique selling point on their website. (What wasn't done)