I walked by the San Francisco Skaters' Showcase today.
[Updated to add:] I went back a week later. The tent and the inflate-a-skate were back again. I guess they weren't there for the San Francisco's Skater Showcase special occasion thingy. I guess they're gonna be there on… weekend days? Sunny weekend days? I dunno, exactly, but I guess they're gonna be around from time to time.