Being that I am 56 years young, there was no money back in the 1960's to shell out for me on extended guitar lessons. I had a few lessons, learned how to read and play "sukiyaki" from Mel Bay 1 and realized then that I was never going to learn the songs of the group that made me want to play guitar, THE BEATLES. So I put down the books, learned every song by ear, and have played by ear ever since and do not need music for most songs that I know.
Now each of my 3 kids are trained to read music and have to have music charts to play. That is tough when I tell them to jam in a certain key.
None of this is wrong as long as the music sounds good.