Hardy Weinberg, from the comments:
I know I have been trolling their facebook page a tad too much (it is actually quite fun, and Ron mentioned me on one of his interviews as a “known leftist”).
It appears you and everyone else was right. About 10-20 people showed up, ironically without dogs. No one from . . . → Read More: BigCityLib Strikes Back: Walk Your Dog In Front Of Mosque Day A Largely Dogless Failure