Now, back to the OP's topic. The way I understand it ago-go dancers pay is based on how many barfines per month she's expected to get.
In Bangkok, 12,000 w/12 barfines would be typical, but on the upper end. A dancer would have 500THB deducted for each BF under her quota.
Some have a drink quota as well. I don't think there's a penalty for not making the drink quota, but if you fall short, it doesn't look good. Of course, they get a certain amount for each LD (60THB on a 160THB drink would be common, but it depends on each location) At the non-gogo bars, I know girls that will easily cross the 200LD mark per month (soi Eric pop's to mind).
In many go-go bars, the dancer will receive 50% of the barfine back, some on their pay at the end of the month.
I've heard of 5 THB/minute penalty for arriving late.
and the list goes on.
Now some girls thrive in this environment, some don't like to go with customers and try to minimize the frequency. The story below is a true story of 2 go-go dancers I met years ago in one of the Rainbow bars in BKK. (Rainbow group, known for high barfines, etc) I met them at a pool hall on Soi 4 one night after this happened. As a group of us took off to Khao San to dance it up, the whole story unfolded.
The girls had a 12,000THB salary, and a quota of 12 barfines per month (600 ea). They'd take a Japanese customer, quote 3K for ST, and go back to the bar once finished and pay the barfine for their friend for that night, and the BF for both of them for the following night. So after 1 girl took 1 customer, they'd both have 2 BFs and 2 nights off. 3000-1800=1200 remaining
The next girl would ST, and the cycle would continue. After they each had gone with 1 customer, they both had 4 BFs each, and 4 nights off. By the time they'd each taken only 3 Short Time customers that month. They'd have reached their quota, securing their full salary, had a bit of spending cash left, and of course all the lady drink money was extra. 3 customers/month each and they'd EASILY clear 15K per month. Now most girls won't be that organized, but you see it's easy to do.
I could expect some go-go girls, w/10K salary, getting BFed only 50% of the nights, 2 lady drinks each night, to clear 15K easily from the bar, and (at 1500/pop) another 22K from the customers. Remember, they often get cash tips too... even 200/day will add up to over 5K more/month. This is all only barfining once every 2 days. Not uncommon in the high season to see a decent looking girl (not talking HOT, just decent) to be BF'd most nights in the month.... where the above numbers would easily double. Also note, that I chose 2 LD's per night. Some can easily get 2 lady drinks/hour.
It all adds up, I guarantee.
Which brings me to a quote I heard LOooooong ago.
There's A LOT of money in Patong.... but you'll never see any of it!