You can make your own plant milk, especially if you have a strong blender. I have made my own flaxseed milk (amazingly flax seeds and water can whip up into a nice creamy milky substance and I add dates and calcium powder and vegan D drops to it. Omega 3s are already in there lol). I have also made my own almond milk and coconut milk. Still haven't gotten around to making my own rice milk but I hear that is one of the easiest to make. Very little ingredients are needed for homemade plant milks. And it's all real food.
As others said, there are a variety of plant milks and some brands have less additives in them than others. For soymilk, if I drink that, I buy it organic with only a few ingredients and always with whole soybeans (some are made with soy flour). Some hemp milks are made with very few ingredients and without carageenan. Check out this list (scroll to middle of table for nondairy stuff) for plant based nondairy alternatives without carrageenan:
I very rarely use margarine or Earth Balance or other butter substitutes. For baking sometimes I just use oil such as coconut oil or extra virgin olive oil. Coconut oil or coconut butter is somewhat of a solid too and can be used in place of butter for some stuff. So can nut butters or peanut butter or tahini. A few times a year I might use Earth Balance. On toast I often have homemade bean spreads or hummus, or applesauce, or salsa, or nut butter.
As a substitute for eggs in baking and leavening:
tofu, flax seeds, chia seeds, hemp seeds, applesauce, pumpkin, tomato paste (for veggie burgers), chickpea flour (make great omelets), almond flour, cornstarch or potato/tapioca starches, agar flakes, plant milk and lemon juice or vinegar for "buttermilk", banana, avocado. Avocado works very well in place of egg for making mayonnaise and for making chocolate pudding (with maple syrup and cocoa powder it makes a very rich frosting or pudding).
Also, just so people are aware, many omnivore foods have carageenan in them. I have looked at food labels on omnivore foods such as mayonnaise, breads, crackers, margarines, and other processed foods and I have seen carageenan mentioned on them quite often. And guar gum, xanthm gum etc. Personally I don't think these particular additives are all that bad as far as health risk unless a person has an allergy or intolerance to them. Carageenan is simply a type of sea vegetable. I have been drinking plant milks for many years and have not developed any strange or unusual problems. Back when I consumed dairy I was sick all the time with digestive problems and sinus issues. My digestion is SO MUCH better as a vegan. I do keep processed prepackaged foods to a minimum though and concentrate more on dried beans, whole grains (millet, buckwheat groats, quinoa, brown and wild rice, bulgur and oats etc), fresh or frozen fruits and veggies, sometimes organic tofu and tempeh or chickpea flour and so on. Stuff like Cliff bars, vegan meats and cheeses, vegan breads etc are treats or occasional foods for me, not staples.
As far as cheese, I am not a huge fan of it and rarely consume the processed vegan cheeses. I might have Daiya two or three times a year. I do however use nutritional yeast once or twice a week and I suppose some would consider that processed. I use it with sweet potato or pumpkin and tofu to whip up a rich vegan "cheese" sauce to go over my baked potatoes or other dish, or add it with almonds or sunflower seeds to my blender and grind up some "Parmesan cheese" to sprinkle on stuff. That's the extent of my cheese usage lol. Once a year or so I like to make my own vegan nut cheese with almonds, nutritional yeast, agar flakes, plant milk, and spices to make a harder sliceable "cheese". I really don't miss cheese at all. I was not a fan of it as an omnivore and avoided it like the plague since 2003 as I would get terrible cramps, diarrhea and bloat. I have found so many other creative ways to make stuff like pizzas (white bean spread or hummus or other tahini based spread makes a great substitute for cheese on pizza), grilled sandwiches (think sliced avocado and tomato sandwiches grilled with just a hint of coconut or olive oil on the bread for grilling), ricotta for lasagna or manicotti filling using sweet potato or butternut squash, tofu, and nutritional yeast, alfredo sauce using ground almonds and plant milk etc.
I think there is a stereotype that vegan food is all processed substitutes of "real" food. Like omnivore food, there is vegan junk food too. But the meat and cheese processed alternatives are not generally vegan staples. I don't know too many people that could afford to eat them all the time. If you look into many vegan whole foods cookbooks and nutrition books you will find a wealth of plant food that is as natural as you can get. Fruits and vegetables and some nuts/seeds can be picked from a plant or tree and eaten as is. Can't say the same for meat and dairy, which has to be pasteurized, skinned, deboned, drained of blood, heated, filtered, and preserved in order to be safely edible. Often animals are fed antibiotics or cheap grains and their natural hormones are laced in the food they become as well. Though dairy milk can be consumed raw, there is a good reason why pasteurization was invented. And the environmental and ethical expense of producing that milk just isn't worth it.