Except the actual core rules aren't on the site. I have gone there raring to buy all the core books. Nothing. They are losing sales left and right from me because I simply can't find them. I want them, I want them to take my money but I just can't find the RULES I need to run those hundreds of PDFs you mentioned. It seems like they want to LOOK like they are trying but not actually putting up the stuff people want. Every edition for everyone? Yeah I guess If you have the printed rules to run those editions.
Nope. They don't care. They really don't care about you. Sorry, but that's the truth and you have to accept it. All of you who refuse to buy the books or pay for Dungeonscape... they threw you a bone by putting the Basic Game online for free... but that's it. That's all you get. If you don't like that... tough. You can go back to playing Pathfinder if PDFs matter that much to you. Or else you can do the final thing as you mentioned and buy a book, rip it apart, and scan it in yourself.
There's really no point in complaining about it though, because they know some of you want that and *only* that. It's been made perfectly clear to them. All throughout 4th edition they heard it... and now into 5th. But they - don't - care. They don't want your money that badly. Maybe they don't want to eat in to possible Dungeonscape subscriptions. Maybe they don't want more PDFs easily downloadable. Maybe it's not that they fear individual people pirating the books so much as they don't want game tables to just buy one PDF and then email it to all of their friends in the group. Who knows.
But regardless of how many times people scream it or call them names saying they have horrible business sense... it doesn't matter. They aren't going to give it to you. Not any time soon. So if you want to play 5E that badly, "give them your money" by buying a book... scan the book yourself... and then put the book in a three-ring-binder so now you have a PDF and a book in your hands.
Cause that's really your only option and it ain't changing any time soon.