In the personal service industry I think folks should give their best at all times. That is how they stay in business tip or no tip. As someone pointed out, the price you pay IS for the service, no?
*thinking about this more*
Maybe the stylist that receives a tip is more likely to give you tips, advice etc. but luckily I come here for the extras. I don't need an extra inch cut off, I don't need an extra wash and all my extra info and could come and get it for $5 and get the BEST info
...oh wait, it went up right?