No, but the fretboards on guitars are usually only oiled and not finished. Ebony and rosewood are incredibly dense and smooth without requiring a lot of filling of the grain, and they (rosewood in particular) exude a natural oil and makes them easy to play. The woods are chosen because they last well without wearing, they exude a natural oil making them easy to play, and finally for looks.
So it's not sound - it's playability.
It's not just guitars. Ebony's used on the fingerboard of violins.
Almost any wood can be oiled, even if few are dense enough. I’ve played many pianos that had genuine ebony black keys, and they never felt greasy like they were “exuding” anything. My buddy Ronnie, who is a whiz electric guitarist, oils his axes’ fretboards. Most of the wear is borne by the metal fret, anyhow.