Why yes, you can "Fix" a charcoal drawing (keep it from smearing when touched) using cheap hair spray, rather than stinky fixatives from the art supply stores. I've been told the hair spray will yellow over time, but I've 30-40 year old drawings that show no color change.

Lately though, I've been fixing my charcoal drawing with urethane spar varnish applied with a brush. Of course your first thought is but but but, the brush will smear the charcoal all over the place!

Ha! not if you apply it to the back of the drawing, let it soak through the paper and hang it up to air dry.