I disagree. Back in 2003 ahead of my first visit I bought what was called a 'Lonely Planet'.
It was all in there in the 3rd or 4th chapter long before serious Internet and Facebook, Thai Visa.com etc. Long before I even set my first foot down on the ground in Don Muang airport I knew about K-bars which is why I've never been in one.
(LP also told me about the bridge across to the railway, where I took the train to Ayuthaya for 9 baht. Spent 3 days there marveling at night markets, boat trips, temples, elephants and dragon boat races with a side trip to Lop Buri. An absolutely enchanting way to enter Thailand - probably still is for newbies. Then I moved on to CM for 3 weeks where I didn't scud around K-bars.)
Anyway to try leaving any venue without paying is asking for a good kicking. Call the police who will at least help you 'negotiate' the price down. But pay you must.