In plain English, a shunpiker is a driver who avoids major highways, especially toll rolls.
The term dates back to the age of horses, carriages, and stagecoaches; and derives from shun, meaning "to avoid;" and pike, short for "turnpike."
The first shunpikers were people who specifically avoided toll roads, either for financial reasons (that is, they couldn't afford to pay the tolls, which often were quite expensive), or as a form of social protest. Most early shunpikers were private citizens rather than stagecoach operators or teamsters, as the latter usually were able to recover the cost of the tolls either by raising their rates or in the form of increased productivity.
Today's shunpikers include the whole gamut of drivers, from private citizens in passenger cars to truck drivers and other commercial drivers. Professional drivers sometimes can save hundreds of dollars a day by avoiding toll roads, especially in places like the New York / New Jersey Metropolitan area, where the tolls are so exhorbitant that the savings realized by avoiding toll roads can outweigh any increases in travel time or fuel costs.
The term "turnpike" originally referred only to toll roads or "tollways." The first toll rolls were called "turnpikes" because the toll gate consisted of a long stick, or "pike," that was "turned" (swung out of the way or raised) only when the driver paid the toll. Many of today's toll roads are still called turnpikes, such as the (in)famous New Jersey Turnpike.
Most early turnpikes were built and financed by private companies. In some cases, the rights granted to these companies were perpetual (that is, the companies expected to be able to collect tolls forever). In other cases, it was intended from the start that toll collection would cease after a specified time, and the roads would be turned over to free, public operation.
In either case, the state(s) through which the roads ran typically retained title to the land, and granted the private companies the right-of-way. The tolls collected were shared between the private operators, the state(s) through which the roads ran, the politicians and bureacrats that the builders had to bribe in order to get permission to build and operate the roads, and the police officials that they had to bribe in order to help enforce toll collection.
The inherent corruption of the privately-owned turnpike system eventually led to its demise: Today, there are very few privately-operated roads, bridges, and tunnels. Most of the early turnpikes have since been converted into free roads, although many still retain the word "turnpike" in their official names. In other cases (for example, that of NYS Route 32), long lengths of road that originally consisted of multiple, sequential turnpikes were combined into free highways, and the word "turnpike" disappeared from the official designation.
Drivers have detested toll roads since the beginning, not only because of the tolls themselves, but also because of the delays caused by the toll collection process. On heavily-traveled highways like those in the New York City / New Jersey Metropolitan area, toll delays can easily reach an hour or more.
Other reasons to hate turnpikes included to food served at the concessions (which typically was overpriced and barely edible), the fuel prices along the pikes (invariably sold at inflated prices), and the monotony.
Finally, many people objected to the essential privatization of public lands for profit that the turnpikes represented. These people rejected the argument that the private funds were what allowed the roads to be built in the first place. (Perhaps ironically, many modern-day shunpikers object to tolls because the revenues often are used primarily to subsidize public transportation, rather than to maintain the roads, bridges, and tunnels.)
Nonetheless, because the turnpikes typically provided the fastest, most direct routes between popular destinations, most drivers bit the bullet and paid the tolls -- and most continue to do so today.
Except for shunpikers.
Shunpikers are people who really hate turnpikes and other toll roads, and often major highways in general. We favor the older, smaller, less-traveled roads, not only because they are toll-free, but because we relish the history and the lesser-known amusements and treasures that we find along the way. We know that we're adding time to our trips, and possibly even spending more on gas than we're saving on tolls. But we're in no hurry; and shunpiking is not just about being cheap.
For the most part, we're just people who are less focused on the destination and more in tune with the journey itself. We try to make every trip part of the adventure, especially when we're traveling on vacation. We're notorious for stopping at garage sales, trying out new places to eat, and looking for oddball attractions in the most unlikely places.
So in the end, being a shunpiker is not (just) about being cheap and avoiding tolls. It's about not being in such a hurry to get someplace that we miss all the interesting experiences we can have along the way. It's about making the journey itself enjoyable, rather than trying to "get it over with" as quickly as possible.