Your argument is somewhat correct but flawed.
Just because one or two drunk numpties may pay 200 for example on a friday night, does not show market efficiencies.
The girls would be better of charging lower prices and seeing more customers to make more money.
Investopedia:
Market efficiency refers to the degree to which market prices reflect all available, relevant information. If markets are efficient, then all information is already incorporated into prices, and so there is no way to "beat" the market because there are no undervalued or overvalued securities available.
You and I have no way to know what all the relevant information might be here.
"She" on the other hand knows whether she is making an optimum (for her) return on her investment given the market she is experiencing. If she is not, she may need to reduce her price to achieve that return, or to settle for a lower, perhaps much lower, income or to switch to a different market.
Certainly other providers "provide" at a lower price, and (presumably) higher volume business model. You, as a buyer, are of course free to buy from them. Others can and will choose differently. In addition, you actually have no way of accurately assessing the actual number of numpties, the level of drunken-ness or the number of nights on which said numpties get drunk and darken doors.
More importantly perhaps, you and I have no real idea about the relevance of any of those criteria on this individuals persons sales targets. Making "more" money may not be as important to this individual woman as seeing far fewer numpties, and, (by her lights), making "sufficient" money, and in doing so having more time to play Call of Duty.
But she is just one data point in that sense.
The whole point of markets is the power of high volume of sale and purchase decisions that go to make it happen. Large numbers of sale and purchase decisions control everything and set parameters. There is no right and wrong answers, there are only deals and no deals.
The intersection point between what someone will sell for and what someone will pay ... IS the price.
If you are really interested in how this works I really recommend "Basic Economics by "Thomas Sowell". Best book on the subject ever written. It'll change your life!