I bought my 2001 Ninja in 2016 with just under 15k on the clock. It has over 50k and is still going OK...ish
my 2008 750 i just bought has 13k on the clock (laid up since 2013) and here's the thing... BOTH OF THEM SUCKED FOR THE FIRST FEW HUNDRED MILES!
Its easy to be alarmed at high milage but very low milage means occasional riders or the bike has been stored for long periods of time which comes with its own set of problems - cracked tyres, cracked rubber pipes, old fuel gunk etc
My initial MPG on this one was like 30 which made me cry but giving it some longer rides out its averaged out around 50 which is much better (especially having to spend more on E5 lol)
I guess my point is milage isn't the whole story. or something.