The majority of plant and animal life on the planet is not edible (at least not in it's natural state) for humans. Many things that are edible by humans are not edible to other lifeforms, for example grapes/raisins, chocolate, onions, and macadamia nuts are poisonous to dogs. There are many things that are edible that most people do not eat. The things people consume varies by culture and availability.
An item by item list of foods that people in other cultures eat or drink that I would not, would take a long time to create, since there are a lot of things I would not want to eat (many things I do not even know about). Here is a list of a few foods/drinks that the Japanese eat/drink, that I personally find to be revolting:
1. Placenta 10000 (or 400,000)- This is a Japanese jelly drink made out of pig placenta. It is touted to be a health drink and comes in at least two flavors; peach and natural flavor. It is supposedly zero calories and is thought to have regenerative properties.
2. Natto - This is a traditional food in Japan eaten for thousands of years, exact date is unknown but some people think it dates to the Jomen period (10,000 bc-300bc). Natto is soybean fermented with bacillus subtilis (a type of bacteria). It has a sticky glue like consistency and smells like ammonia. This is thought to be very good for you and modern medical science agrees.
3. Sashimi - This is generally raw sea food, though beef and chicken sashimi does exist. There is some danger in eating raw meats, some are supposed to be eaten still alive (frog sashimi the heart is considered a delicacy and is often eaten while still beating) and some of it can very easily kill you (fugu is a very poisonous fish that extreme care has to be taken to prepare it for consumption and several people die each year from eating it).
4. Seaweed. There are many types of seaweed and seaweed is generally very nutritious. Take Mozuku, a stringy and soft seaweed naturally found in Okinawa. It looks pretty disgusting but it contains sulfated polysaccharide (Fucoidan) which is used in cancer treatment aid health supplements (also enhances T cell activity), and with the vinegar sauce it is usually served with it kills E.coli bacteria.
5. Milt - The milt (shirako 'white children') of anglerfish (anko) and pufferfish (fugu) which are considered a delicacy. For those of you who might not know what milt is, it is the seminal fluid of the fish.
6. Marine mammals. It's no secret that some Japanese people eat marine mammals such as dolphin and whales. This is mostly done because Japan is an island nation and those are some of the easiest acquired sources of red meat.
I've eaten natto, sashimi, and seaweed. Natto and seaweed, while good for you just taste bad. Sashimi is raw fish/meat; I don't much like seafood and prefer the meat and seafood that I eat to be cooked. A drink made out of pig placenta and fish semen sounds too distinguishing for me to even contemplate trying.
As for marine mammals, I can give a lot of reasons; they are fairly intelligent creatures, being at the top of the food chain has caused them to have a higher build up of pollutants such as mercury, dolphins occasionally save people, my culture finds the eating of them to be taboo, there are many foods more energy efficient and sustainable (some species of whales and dolphins have gone extinct and others are endangered), etc. The main reasons being my morals are against eating them (though I do not condemn those who do so). I eat other animals such as pigs (pork) which are also fairly intelligent pack animals. They are far more intelligent than most people credit them as being (cleaner as well) and unlike the dolphins, which live mostly a life out of captivity, pigs often live very terrible lives (that is an understatement and if you were wondering I do feel guilty for eating them).