The EA are, quite sensibly, going to check places that they can do quickly and easily. Places where they are going to get the maximum number of individuals in the shortest time possible. The reality is that it means busy match type commercials, big carp day ticket waters, popular stretches of river with good access (or boat access) and big matches.
I've been checked in all of those situations, from the Trent (where they arrived by boat) to a 48hr carp match. If you fish little club waters, or stretches of river, miles from anywhere, the chances of being checked are minimal.
If I wanted to find the greatest number of anglers, I certainly wouldn't be walking the banks of my local rivers, nor would I trawl the local club stillwaters. Chances are that I could walk and drive for miles and wouldn't find a soul. I know full well that I could drive twenty odd miles to two of the biggest commies in the area (they are just a few miles apart). On the average weekend, or bank holiday, I'd get several hundred anglers in a couple of quick and easy hits. Even midweek on a foul day, you'd probably see more anglers than you'd see in a week on thirty miles of the local river.