Where the hell do you live that you can get 20 streetpasses in a day? The maximum I have ever gotten was when I went to the city where I got like 6 ._.
Well during StreetPass weekends at Nintendo Zones I could get quite a lot! But honestly at all the regular places I'd go in a week there were "regular" StreetPassers who I would see. Average would be 6 per location. I'd bring the 6 in, and go to one other place, or at a mall or something and get 6 more.
But the past 2 weeks its been almost nothing.
I looked at the AT&T site and apparently Hilton hotels are no longer part of the wifi, so that would explain this past week. And Hampton Inn is no longer showing up either, and I used to drive by and get some there, but apparently not.
Maybe this isn't a Nintendo thing, but rather an AT&T issue.