I like how the unit of size was football pitch. I guess around the world it's assumed that the reader has intimate familiarity with lining up sporting fields but can't handle things like a metric system.
It's nothing to do with the metric system. Can you visualise 330m, or would it be easier to visualise three football pitches (or insert any other familiar large area)?
I know how much that would cost me in server farm, apartment, and retail space. My exposure to a magnitude (or a collection of) meters far exceeds my exposure to a large area reserved for multiple say, soccer fields, or any intuition on really how large they are.
To be honest, whenever I hear something like "17 football fields" I go look up the distance of a football field to try to understand what the heck they are talking about. They might as well have phrased it as the distance a snail travels in the time it takes for a tea-candle to burn.
I use metric and imperial units every day. I intuitively and immediately know what 330 meters is in almost any context.