I also tend to find I underestimate distances in grid systems. I think it’s because in European cities I estimate distance by the number of distinct shapes I can remember on the way there. In a grid, I think my brain smushes all those identical block shapes into one. In a similar way to how time flies when doing a repetitive task.
In a similar vein, I find the Las Vegas Strip is incredibly disorienting with respect to distance. You're used to buildings being of size approximately X and in Vegas the casinos are 10X. So you think--oh, that's just a couple of buildings away. 30 minutes later you're still walking (in the sweltering heat).
And I, by no means mind walking, though there was the time I went to Vegas on a business trip and was on crutches with no weight on foot allowed. Though the high point was that a porter showed me how to use the crutches more effectively; he was an (aspiring?) ballet dancer who had apparently spent more than his share of time on crutches :-)