IW,
Charter taxis would go out of business if they refused to accept $5us for some of their trips. I dont know of many drivers would refuse us$5 for many of their trips.
When you ask a route taxi to go off their route, then it automatically becomes a charter. The protocol is simply to ask them - such as "can you take me to "ABC" for an extra j$150?"
Place the blame for the $25us you paid to get to HiLo on capitalism. Apparently at that point, you thought us$25 seemed like a fair price. Dont blame yourself or the driver - it was a learning experience.
And knowledge is power.