OTWO - You probably came off as too spiritual. They probably dropped hints but you and your wife didn't catch on so they didn't push it any further.
Anyway...I think its more common than believers think. I know of several groups of swingers in different areas over the past 10 years.
One congregation used to confuse the living daylights out of me...because so many of the kids had a different the last name than their parents and that of a JW male in congo or of one in a neighboring congregation. I simply thought everyone was cousins or something...
Then one day this older single JW lady, who prides herself on her lifelong chasity, gave me the lowdown after I talked about how confusing it was with the names. She told me to be careful about what I say because everyone is practically related to everyone across the two congregations. Apparently about 7 or 8 years ago there was a lot of wife-swapping between these two neighboring congos. A number of folks were df'd, many of them divorced their spouse and married one of the other folks from the swingers circle. Just about everyone was reinstated or got their privileges back by 2005.
This congo was interesting...the elder body comprised of 2 fathers and their sons...practically no one went in field service...monthly avg of 3 hours...2 phantom pioneers...they were very happy to get a pioneer (me). Here's the thing...brothers in this congo winked at me all the time...friends of mine told me that it just meant the brothers thought I was cool...if I were funny and fat I would believe that...plus it felt like an invitation.
Anyway, one of the elders eventually told me that it would be best if I went to a different congregation...so I did and a crazy accusatory letter followed. Little did I know it but that was the beginning of the end for me and the JWs.
JWs are a real trip...LOL...bunch of freaks.