Sukkot while traveling is problematic in several different ways. However there may be many recent innovations with the sukkah (with such things as the travel sukkah and pop-up sukkah being a possibility), which leaves to problem of where, and when to eat, and while on the road, these dilemmas can be worrisome.
Are there any exceptions for the traveler to eat in a sukkah?
It is said in the Gemara that those who travel by day are exempt from the sukkah by day but are obligated to at night, and that those who travel by night are exempt at night but obligated in the day, and that those who travel both day and night are exempted in both those times as well. The principle behind this is that it is normal for one to travel without permanent dwelling, however when the traveler finishes for the day, it would be time for him to search for a sukkah. This is why day-travelers are exempt from sukkah by day, and night-travelers, at night.
The Gemara also makes a distinction between regular travelers and one traveling for purposes of mitzvah. A mitzcah traveler is exempt from the sukkah both by day and by night, because one who is already prior engaged to a mitzvah is exempt from a secondary mitzvah.
Are all travelers included in these exemptions?
The Gemara states that travelers for business should be exempted, but not travelers seeking pleasure. The reasoning behind this is that it is customary for one to leave home to do business, but it is not a necessity to leave to comforts of home for pleasure (assuming that home, in itself, is pleasurable enough), and that it merely seeks to satisfy only a desire and no other purpose.
Should one go on a journey knowing that there are no sukkahs along the way?
As stated in the previous paragraph, one would be permitted to journey and would be exempt from searching for sukkahs at certain times of day given that there are any, if one travels for business or for mitzvah purposes. Defining what constitutes a mitzvah purpose is another matter altogether, however it has been said that traveling for livelihood could also be considered a mitzvah purpose. Another mitzvah is that of visiting relatives, most pointedly of visiting parents, where the mitzvah of honoring your parents are concerned. Travelers with such objectives are exempt from the sukkah also.
It is cited repeatedly, that traveling for pleasure is deemed optional traveling, and should not included in said exemptions.
Since Sukkot requires that any kind of eating should be done in a sukkah, is there any difference between actual meals and snacking, when it comes to eating outside of the sukkah?
The entire discussion (and often, confusion) in regards of exemptions from a sukkah relates to the activities that are absolutely required to be done within it. While doing all of one’s daily, regular, activities inside a sukkah is very commendable, the only activities that demand a sukkah is eating a meal and sleeping.
Such is a dilemma for travelers, as one could not very well be bothered to search for a sukkah while on the road when one is hungry!
To eat less than a ke-beitzah (an egg’s worth) of bread, or less than a ke ‘viat seudah (a meal’s worth) of grain items, such as cookies or cake, would constitute a snack, and these are allowed to be consumed outside of the sukkah.