BS. Guy pulls up with his cab and has to wait 3 to 4 hrs for a fare. I don't buy that.
Ever driven a cab? I have; and it's entirely possible.
One way to make good money is airport fares, as they are usually long rides with big tips. The problem with them is that at most major airports, the wait in line, which is a highly regulated affair, is quite long.
Other options (hotels, bars, grocery stores) involve less waiting but are shorter rides with smaller tips.