Actually not a coincidence. The meter was originally defined as the length of a "seconds pendulum" (a pendulum with period two seconds). The half-period of a pendulum of length L is pi * sqrt(L/g). Set L = 1 and solve for g, and you get g = pi^2.
This doesn't work exactly because the meter eventually wasn't defined as the length of the seconds pendulum but rather as one ten-millionth of the distance from the equator to the North Pole - which turns out to be a few millimeters longer - but the idea for using something meter-sized as a unit of length came from the seconds pendulum.
This doesn't work exactly because the meter eventually wasn't defined as the length of the seconds pendulum but rather as one ten-millionth of the distance from the equator to the North Pole - which turns out to be a few millimeters longer - but the idea for using something meter-sized as a unit of length came from the seconds pendulum.