How do people manage to get scammed by taxis at Swampy?

[scubascuba3]

I use GPS on my smart phone to track where the taxi is going relative to where I think he should be going. One taxi a week a go tried to take the long route and get stuck in traffic. I had words. Another taxi (perhaps one of the few really honest taxis) took me from Nana to khao San road on meter for 75 baht, others were quoting 200-300.

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