Cigarettes were indeed given as part of the standard ration, up until the 1970's when they were removed as the dangers of smoking became more evident. The US Army utilized several types of rations during WWII.
"A" ration: Hot, prepared food made at a field kitchen behind the lines; could vary depending upon what food was on hand
"B" ration: Unrefrigerated canned food prepared at field kitchen. "10-in-1" or "5-in-1" rations were variants of the "B" ration
"C" ration, for general use in the field when food from a kitchen could not be brought up. An individual "C" ration for a soldier for one day consisted of three "M" unit cans, three "B" unit cans, and an accessory pack wrapped in sealed butcher paper. A meal was one "M" unit can and one "B" unit can. Later variants of the C-ration were in use through the Vietnam War.
Three 12-ounce "M" (meat) unit cans. A meat entree which could include "Meat Stew with Beans," "Meat Stew with Vegetable Hash" (later dropped), and "Meat Stew with Carrots and Potatoes. Added in late 1943 was "Meat and Spaghetti in Tomato Sauce." Making their appearance in 1944 were "Ham, Egg, and Potato," "Meat and Noodles," "Pork and Rice," "Frankfurters, Pork, or Ham with Beans, and "Chicken with Vegetables." Coming around in 1945 was "Beef Stew with Vegetables." An experimental "Mutton Stew with Vegetables" was dropped.
Three 12-ounce "B" (bread) unit cans. Hardtack-like energy-rich crackers or biscuits (amount varied, usually 4-5) along with three sugar tablets and three dextrose energy tablets
A accessory pack wrapped in sealed butcher paper, containing a piece of candy or gum, sugar tablets, water purification tablets (briefly in 1945), toilet paper, a wooden spoon, nine cigarettes, and a book of 20 matches
"K" ration, a partly canned and partly plastic-wrapped ration for short term use and not designed to be used for an extended period of time. Each ration unit was compact, packed in a rectangular brown cardboard container. They were intended for issue to assault infantry, tankers, and paratroopers in strenuous situations. A day's sustenance consisted of one Breakfast unit, one Dinner (lunch) unit, and one Supper unit. Later in the war, the style of the units' packages were changed from plain cardboard to have colorful red (Breakfast), blue (Dinner), and green (Supper) trim to increase morale.
The Breakfast unit consisted of chopped pork and egg yolks or ham and egg, biscuits, 15 dextrose energy tablets or malted milk candy (early) or oatmeal and a dried fruit bar (late), coffee, sugar tablets, water purification tablets, toilet paper, a wooden spoon, a can opener, and four cigarettes with matches
The Dinner (lunch) unit consisted of biscuits, a cheese product (American cheese, American cheese with bacon, or American and Swiss cheeses), 15 dextrose energy tablets or malted milk candy (early) or 5 caramels (late), lemon (early), orange (mid), grape (late), or cocoa (late) drink powder, several sugar cubes (early) or a packet of granulated or compressd sugar (late), salt, a wooden spoon, a can opener, and four cigarettes with matches
The Supper unit consisted of canned pork with carrot and apple, or beef and pork loaf, a bouillon cube, a miniature "D" ration bar, coffee, sugar tablets, a wooden spoon, a can opener, and four cigarettes with matches
"D" ration, an emergency "chocolate" (actually chocolate mixed with oats, stiffeners, and other vitamins) bar designed to be eaten in emergencies only. One of the requirements for its design was that it taste "a little better than a boiled potato" to prevent soldiers from eating it when they weren't supposed to
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