I think those are guitars that were actually sold and that those were the (sometimes incorrect) prices paid at different points in time and not adjusted for inflation.
Hendrix guitar was (not surprisingly) bought by Paul Allen of Microsoft fame and he can certainly afford to pay it.
Garcia's Tiger was bought by Jim Irsay, owner of the Indianapolis Colts. He has an extensive collection that also includes guitars owned by George Harrison, Elvis and others. He too can afford it.