I like my hairdresser, but I'm still not going to tip her.
That's rather selfish. Why won't you tip her?
I'm just too tight-fisted.
You said you like your hairdresser. So, if you think they do good work, then you should leave a tip for them. I'm sure they would appreciate it.
I'm already paying her for doing my hair. Why should I tip too?
Tipping her would show that you appreciate the hard work she puts in. It's a common practice to tip people who work on your hair. If you don't tip her, she might be less inclined to want to book you for future appointments.