I’ve pondered the question and the most reasonable metaphor I’ve located is:
a table is a surface on which items are placed
This seems a little broad, but maybe that was all of the thought put into the naming of the concept. I’ve also searched Google and Wikipedia a bit and have not found a record of the inception of the term.
Table is a word with more than one meaning. In this case, a table is a sort of chart, with information arranged in rows.
Wikipedia says:
“Historical relationship to furniture
In medieval counting houses, the tables were covered with a piece of checkered cloth, to count money. Exchequer is an archaic term for the English institution which accounted for money owed to the monarch. Thus the checkerboard tables of stacks of coins are a concrete realization of this information.”