They really do help. My main symptom seems to be horrible, searing heartburn that can stop me in my tracks. There is some intestinal gas as well, but that is not the main problem. The normal symptoms of lactose intolerance are produced by undigested lactose being fermented by bacteria in the colon. That's a long way away from the stomach.
Digestion is normally one way, but occasionally there is a backing-up, or reflux, of material.
Heartburn is the best known example of this. Heartburn can have many causes, but none of them that I know of have anything to do with lactose. Few people realize that fats and chocolate, along with smoking and certain drugs, can cause the esophageal sphincter to leak. When you add that to coffee and alcohol, both of which stimulate acid production in the stomach, you have a huge range of common substances that can cause the problem, or at least make it worse. So I'm stumped.