Mars is lovable because of the ancient staff, visible in the wall portraits and on some mornings; the affordable diner prices (as opposed to chi chi pseudo diner inflated prices); the atmosphere; the burgers; the availability of versht with standard breakfast; the corn muffins (raptures); the milkshakes and the location and hours.
People who deny the tastiness of Mars cuisine either haven't had a Mars burger or are unable to taste the authentic greasy goodness of a diner breakfast served at less than $7 all inclusive, because they think you get what you pay for. At Mars, you don't; you get ever so much more.