You think they are equally going to be okay with losing data ? Or do you want to try again.
Let's add some more companies: 37Signals, DHL, Dropbox, Evernote, UPS, Kayak, LastMinute, Orbitz, Continental, Mint, Quora, Tumblr, Techcrunch, Slashdot, NYT, NBC, Reuters, Wotif, Zappos, Wikipedia, Youtube.
You still think any of these companies would tolerate loss of ANY data for ANY reason ?
For example, taking the first company on your list that actually deals with real stuff in the real world rather than just running a website, DHL, here I see http://www.oracle.com/us/corporate/press/037809 - they're an Oracle shop. I could continue but I think I've proved my point.
So before you get all starry-eyed about these amazing companies and their amazing MySQL installations, understand that you are starting from a false premise. Oracle - for a cost - provides some powerful capabilities (e.g. stretch-RAC). Is it worth the money? Well, it comes back to what your data is worth. This incidentally is why some organizations cling to paper forms - it's cheaper to re-key the data than build out the infrastructure to do it all online...
 Tho' if you think you need this, what you probably really need is DB/2 and Sysplex