Follow this advice. If you are working for an American company bribery is a horrible idea and in a situation like this would likely be used to make a case against you. The only exceptions made for bribes is if you feel like your life may be in immediate danger, in which case you are supposed to report the incident immediately to your employer and the local embassy.
The other downside to bribery is if you have money, you become a real target as everyone will start harassing you in exchange for bribes.
Bollocks. Tipping is predictable and normative. You assume 15% when going to restaurants, and roughly the same amount in other contexts, like getting a haircut.
No one is fleecing you, and the costs are predictable using basic math.
You may be thinking of Lobbying, which is a totally different phenomenon.