Actually, no. The cause is not enough exercise/work. You can eat as many calories as you want as long as you expend enough energy to compensate, anything less makes you fat.
See how easy it is too justify the exact opposite. I can actually say that my version is more accurate to real life because you eventually reach a point where you are spending so much time expending energy that you cannot consume more calories and the system can reach equilibrium. You cannot go the other direction and expend so little energy that you can eat nothing. Besides, sitting on your ass all day and eating almost nothing will have its own consequences (poor circulation, bed sores, atrophied muscles, etc) whereas leading an active lifestyle generally prevents those problems.
As for the rest of your post... yogurt makes people to gluten sick because it contains glue? WTF. Gluten is a naturally occurring protein found in many whole grains (whole grains are good for us, right?). It has nothing to do with glue.
At the end, human gullibility and idiocy may mean that unless it is forbidden some will abuse it. Ah yes, the old "we know better and must protect the ignorant from themselves" routine. IOW, let's treat everyone as a slave lest they harm themselves.