Haircut or Shave or ...

Everytime I go to my barber, he asks me whether I want a haircut or a shave. I was getting tired of repeating that I need just a haircut. So this time, I went to the barber clean shaven. Again, he asked me whether I want a haircut or a shave. Again, I told him that I need just a haircut. Later, I wondered, what the hell was he offering to shave anyway?