Ok, today's annoyance...what's the hatred towards "Mione" in fan fiction? 

I have seen it derided because it shows "laziness" or it's not canon or some such.  Others get all bitter because they think it shows a lack of respect. 

Let's think about those. 

First, humans are inherently lazy when talking, generally.  Especially in modern verbalized syntax, which is what we are writing when one writes dialog for characters that have been born in the last thirty years or so.  They are not all Dumbledore who grew up in the Victorian age, who uses Nymphadora for Tonks, instead of "Nymph" or even Tonks, which actually shows a touch of disrespect because it is not what she says she wants to be called.  In my recollection, Hermione has never weighed in on the issue on one side or another. 

Mione, depending on the pronunciation, is either 3 or one syllables.   If used at the proper time, it could be used as a barely awake alternative, or a post-coital sigh or something similar.  Times at which the brain barely works anyway.  Also, if used as an appropriate diminutive, a "pet-name" if you will the term 'works'.  And unlike popular opinion, that is not always during some special, happy moment, but also during times of stress...or occasionally just because. 

A second reason that I have seen mentioned is that the name “Mione” is not canon. 

Honestly, who gives a damn, really?  Canon is, at this very instant, unless you are an ardent defender of Mugglenet’s possibly warped version of reality, a muddied morass of half-imaged “facts”, mangled perceptions, and possible, outright lies.  There is nothing set in stone until the word “scar” appears on the page about 8-900 pages in and perhaps not even then.  In canon, recently, we have seen characters abandon friends they have held closer than family since they were eleven, fire possibly lethal spells at each other, and I’m not talking about Harry’s attack against Malfoy, and set aside their basic core beliefs and values in favor of suddenly chasing after a moment’s pleasant snog.   It is more “canon” that say, Hermione is close enough to Harry to allow him, and only him to call her by a diminutive ?

Which brings us to lack of respect, perhaps. 

 This in some ways goes back to my original point, is it really a lack of respect?  Very few people that I know of are called by their actual full names.  Some are, I agree, but how many Michaels or Roberts, are called Mike or Bob?  How many Maxines, Max?  If some one calls me Mike, instead of Michael, that’s just fine with me.  Respect is far more and less than a simple dropping of one syllable from a name, and even as fucked up as their relationship may have been in HBP, generally even the most ardent R/Hr shipper don’t claim that Harry lost any respect for her. 

 Mione, at least as I have used it in several works, is a term of endearment, not as her name, and as such shows the utmost of respect. 

 Some may disagree, and that is fine.  I respect their opinions, even if I do not share them.  After all I think that trees burn or can get cut down, and the mutual attraction between the hero and the heroine in the series, i.e.…. gravity, is.