The Irish are probably the worst. Give them an alphabet of 26 letters and they run mad. This article names one "Fionn MacCumhail" for example. It took a moment or two to realise that yer man here was talking about someone I thought of as "Finn McCool" or similar. It was actually years before I twigged that "Dun Laoghaire" was the same place I'd heard spoken of as "Dunleary".
The Welsh do it like mad: for God's sake.
And how many times have I been asked by American tourists, for Lye-sester Square? (Leicester Square, pronounced "Lester").
But am I really asking for standardised phonetic spelling? No, far too dull.
More examples from around the world, please.
*pronounced "Heysburra". It's in Norfolk you know, but just barely.