(Despite what is about to follow, I solemnly declare that I am not a germophobe, but I will admit to having a healthy appreciation for sanitation and order.)
To be explicitly clear: feet are disgusting. I seem to be one of the civilized few in the western hemisphere who understands this nauseating fact. In many other countries it is considered uncouth to put your feet up, to put one foot on top of a knee, or to even cross your legs (because it shows the bottom of your feet). As a matter of fact, these same matters of etiquette used to be in force in the colonies around the time of the Revolution. I suspect that the practice of elevating the feet originated and spread like a plague from the backwoods of someplace where cousins are betrothed to each other.
Everywhere I turn, people are emphatically fondling and groping at their feet. They seem to have a fetishistic obsession with their lower phalange. They sit with one foot up on a knee or with their legs tucked in so as to bring their subconsciously favorite play-pal intimately closer. They then proceed to affectionately rub the sole, starting from the heel and moving forward until their fingers interlock with their toes. Sometimes they gently stroke the top of the arch. I often see them mindlessly picking sweaty toe lint from under their toenails while they watch TV. The sight is utterly repulsive. They give the impression that they have no understanding of cleanliness or order.
Feet belong on the ground, not in your hands. That is why they are attached at the lowest points of the body, namely, the ankles. Feet are made to wallow through the filth of our travels. They wade through the mud on river banks. They sit in stuffy, sweaty shoes. They trod on grass that has been fertilized by beasts of the field. Think about where feet have been and you will begin to understand why feet should remain on the ground, whether they are covered or not.
Never should feet be placed on an armrest. An ARMrest is made for ARMs, not for FEET. A FOOT should be rested on a FOOTrest. When my siblings were younger they would run around and play on the back lawn barefoot. The dogs would often do their business on the back lawn, whether it was simply marking their territory or dropping a heavier deposit. Though the heavier deposits were removed, you could still imagine the residue left behind. My siblings were oblivious to this horror and would come into the house wearing the same feet they used to walk on the same lawn the dogs did their business on. Then they would lounge on the couch with their FEET on the ARMrest. Sometimes they would watch TV upside down with their FEET on the HEADrest. For me, this effectively destroyed any luring appeal the couch had as a napping spot.
Sometimes I would see my siblings playing with their feet. Then they would suddenly get up, walk over to the cookie jar, and, to my greatest dismay, with the same polluted hand they used to pick their feet, they would extract a cookie from the bottom of the jar, thereby contaminating the entire contents. To this day I cringe at the thought of those delicious chocolate chip, joy inducing cookies having vulgar ingredients added to them, namely of foot sweat, toe lint, heel flakes, and possibly a light seasoning of dog deposits.
If you have been convinced as to the unsanitary nature of feet, then I will share this secret of sanitation: foot maintenance should be conducted within the confines of the bathtub, not on the couch or at the kitchen table. Furthermore, if any part of the body above the knee comes in contact with any foot outside the sanctuary of bathing, it should be purged of uncleanliness by a priest with holy water and be equipped with a plastic cone around it until the time of cleansing should be fulfilled (about seven days) to avoid further spreading of the contamination.