I was debating with my brother whether they had sukkah hops in Europe, and failed to find a good answer via Google Books or Scholar.
- Is it a specifically American institution?
- What's the first recorded sukkah hop?
What I'd seen around the blogosphere was that it was an innovation by "Rabbi" (he was never formally ordained) Shraga Feivel Mendolowitz intended for Torah UMesorah community day schools that were open on Chol Hamoed (probably in the 1960s, I assume). Some of the students were not observant and didn't have a sukkah at home, so they'd take class trips to see people's sukkahs.
At some point later it morphed from a school activity for the less-affiliated to a social, on-yom-tov, activity for the more-affiliated.