There is absolutely nothing funny about hail. In the matter of minutes, it can destroy a year’s worth of crops for a farmer, cause thousands of dollars worth of damage to a car or home, and kill people; however, the way we refer to hail is humorous.
Most references to hail that I’ve seen in my 24-plus years of meteorology has been in terms of either money or sports. Hail is either dime sized, nickel sized, or quarter sized, or it’s the size of ping pong balls, golf balls, baseballs, tennis balls, or softballs. (For the record, many reports of hail are over-estimated–it’s human nature to over-dramatize an already dramatic report). The only exception to the sports or money references seems to be food, such as grapefruit-sized hail.
Speaking of food, there have been many humorous references to hail, most notably in my mind is David Letterman’s (who was briefly a tv weather man in Indianapolis) references to hail the size of canned hams.
This site (Hail the Size of God) includes some other entertaining reports of hail from around the world, including the rare dry-roasted-peanut-sized hail, hail the size of babies’ toes, and hail the size of spanish olives.