I was surprised by that as well. I thought the water usage for my pond would be the same or less than running sprinklers since I live in a desert. As it turns out, I used twice as much water in July this year as I did in July last year, which was before I had my pond. Evaporation has been terrible for me - I'm adding at least a couple hundred gallons every 2-3 days just to keep the pond full. Nothing around the pond gets muddy unless the sprinklers have run, so I don't think I have a leak - just good old 100+ degree Fahrenheit days.
It's expensive to have it professionally drilled too. A few years ago I was thinking about buying some raw land and trying to live off-grid there with a well, septic system, and solar power. The well would have to be 200-300 feet deep and you had to get all sorts of approvals and applications and tests done before they'd even let you start drilling, then you had to pay lots of money - the deeper the well, the more you paid - and you couldn't even be sure you'd hit water where you chose to drill. Between that, the rules about septic tanks and their placement, and the washed-out road at the top of a steep cliff to access the property, we decided to just stay were we are in the suburbs.