Playing from sheet music doesn't in any way shape or form imply that you play robotically without emotion or feeling. In fact playing from sheet music and sounding like a good musician requires the ability to apply a great deal of feeling and depth.  Even the simplest etude can sound incredibly beautiful depending on whether the musician can put feeling emotion and depth into it, the way he may apply vibrato to certain notes, the way he may shape his musical phrases, etc. This is what separates a true artist from merely a technician, regardless of whether you play from sheet music or by ear.

I have noticed this with many soloists,kl if you listen and compare you will notice they all play often the same piece of music differently even though they are reading from the same sheet music.