The art of looking without looking...
Colombia, by my best evaluation, is as close as a country can get to pure capitalism in this day in age. Any of those right wing economists (ahem Kerpen types) who were genuinely honest, would seek to compare the regulated US system to a country like Colombia just to see what it's really like. I'm sure they'd find their "glorious economic paradise" to be a polluted and at times dangerous place that wouldn't resemble their own ivory tower inflated sense of heaven. Instead, they'd find hard working local and national governments struggling to rein in some of the abuses that deregulation entails, while under tight fiscal constraints. But the rightwingnut-o-sphere will never pursue that type of inquiry because the true nature of ideological politics and pseudoscience is to ignore test cases that dispute your beliefs and trumpet theory when countless case studies indicate your ideology is bankrupt.
Ahem, anyway, one of the manifestations of free market capitalism is that you can literally buy stuff everywhere. If you're walking on the street, you won't go more than 1 block in any direction without the option of purchasing beverages, foodstuff, tobacco, or other consumables in whatever minimum or maximum quantity you desire. At times, it can be quite useful.
Alternatively, if you are driving down the street, you will literally be assaulted by street vendors hawking any number of goods that you may or may not need. Consumables are common, but so are maps, garbage bags, plants, flowers, costumes, cds, and pretty much anything else that one can strap to their body and hawk on the street.
In addition to street vendors, there are a medley of beggars or "entertainers" that may or may not be rude asses, but at the least, are more annoying than anything else. This group is followed closely by the window "washers" that do little more than more dirt around your windshield with an ancient rag. Their scam, not entirely clever, is to launch into a window washing whether you want it or not and then act offended if you don't pay them. They can usually be brushed off with a honk of the horn or some extremely rapid "No, no, no, no"s coupled with hand gestures.
The point is, while these phenomena can be annoying, they can be useful as well. You never know when any given vendor is going to have something you need or want, so it pays to be on your toes. However, staring at the item in question is a definitively bad strategy. First of all, if you're really interested, you don't want the vendor to realize your desire. The art of bargaining demands that one act semi-interested as a means to lower the cost of the good in question. Alternatively, if one is not really interested in making a purchase, but the sale of a particular item brings shock, it does not behoove to stare at the item. The vendor will immediately charge your car and start jabbering in incomprehensible spanish which will leave one's head spinning.
The solution, of course, is to use the corners of your eyes to slyly check out each vendors goods. If you see something you're after, you can begin the bargaining process. Assuming you don't give up your hand, you have the pole position as the vendor wants to make the sale before the light changes and you're gone forever. Alternatively, if you don't see anything you like, at least you spent a few seconds "window shopping" while you waited for the light to change.
The same holds true on the sidewalk. If your need is high (when I needed an umbrella in a deluge, for example) and the vendor knows is (wet hair and face), you are pretty much going to overpay for what you desire. Score one for the street vendor. If, however, you are coy about your desire, it's possible to score excellent goods for a very reasonable price with the added benefit of saving you a trip to the local supermarket - something that can be frustrating in it's own right.
Of course, I'm a total novice when it comes to bargaining - but this is a basis on which I shall build on. I have a long way to go before I can top my wife bargaining down the price of her engagement ring, but I'll get there someday!