I've probably been to 49 of them with the military at one point or another...
After considerable consideration, I decided that such a flippant answer does deserve a serious response. With respect to the military comment, unless you were a very well-traveled military attache or a very transferable Marine guard, I doubt very much if you have been in many of the countries that I can think of. However, some examples might be in order.
My wife's former college roommate is a missionary. In order to get her mail, she has to pay the postman a bribe. Note, this is mail properly stamped and does not need any additional postage. If no bribe, the mail is returned as "undeliverable" regardless of its origin, which typically is the U.S.
My oldest brother was trying to bring some filming equipment into a country to promote awareness for aid to children. Three attempts were made. The first attempt resulted in a demand for $10,000 U.S. to be paid to get it released from customs. The last attempt resulted in a demand for $100,000 U.S., in cash, for it to be released from customs. Despite repeated requests to the American Embassy, the filming equipment was never released to be brought into the county. With the help of the Embassy, they did manage to get the equipment shipped backed to the U.S.
I had a friend whose family lived overseas. They had a fire destroy most of their belongings, and friends and supporters here in the U.S. shipped replacement clothing and household goods to them. The customs officials refused to released the barrels without payment of a bribe, cash in U.S. Dollars. After 18 months, and the assistance of the U.S. Embassy, they finally managed to get the barrels released without payment of a bribe. The Embassy was told that the main reason was that the customs people needed the storage room.
An organization my oldest brother was aware of needed to get some equipment into a country very quickly, and deciding to speed the shipment, agreed to bribe the needed officials. From then on, everything the organization tried to bring in required bribes. After two years of this, the organization needed to pull out of the country, as the bribe amounts could no longer be concealed by accounting measures.
There appears to be an automatic assumption on the part of Traveller players, and role-playing gamers in general, that they are never on the receiving end of this sort of activity. After all, if a Game Master actually did something like this, his players would not be very happy. Therefore, just about anything goes in a gaming situation, as players first assume that they are immortal, and second, that they can do just about anything.
How would a session go if a group landed on a planet, and decided to make contacts with the local criminal elements to acquire some equipment. Their clothing, behavior, and accents clearly mark them as being from offworld. While in a bar, they have a few drinks. They then wake up a few hours later, the male player characters stripped to their underclothing, and in the cargo hold of a labor ship heading for the local asteroid belt as conscript asteroid miners. The female player characters are somewhere else.
Or maybe the players are bringing in some grav equipment to be used on the planet. They leave the starport area, are greeting by the local law enforcement officials, and informed that their grav equipment has been seized by the local government as needed military supplies. No compensation will be paid.
You are the owner of a Free Trader engaged in speculative trading. You land on a planet and get this terrific broker who is sure he will get you a 40 per cent bonus on the standard price. He then pays you only the standard price, and pockets the bonus proceeds. Your problem is then compounded by being told by the local longshoremen's union that to move your containers off of the starport to local shipping agencies will cost an extra 10,000 credits per container, payable in cash in advance. Otherwise, your containers do not move. Complaining to the starport authority does no good as they view it as a union matter and not their business.