I never understand it. In an online environment where we interact almost exclusively through text, people read my name and immediately type something completely different. I get "Acadian" a lot, or "Acakian", or any variation except for Acacian. I can understand mispronunciation if you've never heard of an acacia tree, but the spelling mistakes baffle me.
I'm glad I'm not the only one.
As for IRL name, I love how people mispronounce it. My last name is "McCalla". It's pronounced exactly as it's spelled - MC-CALL-A. But I get a lot of "MC-AL-A". My favorite was when I went to a clinic in a predominantly Hispanic neighborhood and the nurse pronounced my name "MC-AYE-A", as in 'pollo' or 'amarillo'.