If there were so many customers and only the one employee it sounds to me like you would have been in for a long wait regardless of whether or not she took a break

So, if you did not want a long wait, AND You have a history of not liking the results at this place then the smart thing to do would have been to go to the other shop in the first place Just be ultra carefelu corsing that street--I mean if you were willing to cross it when she took her break then you ARE willing to cross it so I do not see how that factors into the story).
Maybe she just didn't care about teh customers and hoped many of you would leave if she dissapeared in back for a while.
Maybe it was when she had to take a break and she didn't feel obligated to tell you this.
Maybe she was feeling light headed and needed to sit for a bit and did not feel good enough to stand around any longer than absloutely neccesary to finish her last customer so she did not take the time to tell anyone this.
Maybe it was soemthing else.
No one knows but this lady, since you did not (politely) ask her.
If I go somewhere that cuts hair for $10 without an appointment I expect the kind of service taht $10 will buy you--stylists told to work fast which often means mediocre results, newer stylists without teh experience to get on somewhere more pleasing to work, minimal serivce and long waits.
If I pay a reasonable price (or much mroe than that at some salons

) and have an appointment THEN I expect to be seen close to when I arrive, have the stylist take the time to give me the cut I want (or explain why what I want is not possible with my hair and reccomend alternatives), have a pleasant conversation with the stylist--or be offered a magazie to read, etc. In other words, while I think he couls have said it in a more accessible way-Bicker is right about this. You cannot go into a bargain place and expect high end service.