I used to hate it back in the early 60s when I bought sheet music that had obviously been transcribed by a non-guitarist - keys transposed to a flat key, and blues given as I I6 I7 I6 .....

I like arrangements to show the chords an accompanying guitarist would play, rather than what the lead is playing, so even though I'm fingering Cs and Es, I'd still expect the arrangement to show a G chord.

Then again, if I'm playing bottleneck, if you play chords you'll come unstuck a I'm probably fretting anything between a six string G and A when the music would show A. Use your ears.