Most stylists are unqualified to do my hair. I feel as if I have to show up at the salon with clean, dc'd and detangled hair and a bottle of my own heat protectant and combs to even get a decent flat iron or rollerset. In addition I save so much money and time by doing these things myself I hardly see the point in letting someone else do it.
If you're going to Lala's or Miss Myra's salon down the block, then yeah, you have to do that, but if you're willing to spend a little extra then you won't have to bring in your own items or wash your hair. REAL hairstylists will look at you like you're outta your damn mind and be like "Nah, ah. We don't do that HERE."