Note that a grid has the same capabilities; you could replace table with grid in their example and add inset: 5pt (the default inset for tables) and it’d look exactly the same!
The difference is mostly semantic: grids are used only for layout purposes, while tables tend to be proper figures in your document following the usual table model (with a table header and so on). Here, a grid would likely make more sense since we’re using its capabilities for layout purposes.
The other difference is that a table has a default of stroke: black + 1pt and inset: 5pt, whereas a grid has a default of stroke: none and inset: 0pt. But you can just change one to the other at will.
For more information, take a look at the following pages from the docs: