No doubt a tourist is always charged higher, but you too exaggerate:
- What does "all day" mean? the point is: how many hours of actual
driving time? you burn fuel only when you drive
- I once went to Barelang and more South to the Kampung Vietnam using the car of a friend of my friend. It was a few hours
driving. I refunded only the fuel and, if I am not wrong, just the fuel costed 200k. So, you see that 70k/hr * 3hrs driving to Barelang and South and return = 200k for taxi service is not too much.
- the standard taxi fare to/from Nagoya to/from Harbour Bay is 40k. To/from Batam Center is 50k. Therefore, 70k/hr is not too much, by comparing to that.