How are townies meeting each other?

[PlayLives]

I started a new hood (no subhoods) and deleted all characters. I created townies (all females) played them for a bit then added them to the townie pool (with shrub). All their memories were erased and they were given the generic townie memories. Ok, so far.
I then created all men townies, played them for a bit and added them to the townie pool. None of the men met any of the females before I added them to the townie pool.

Now when I play my playable sims houses, who I have yet to send to a community lot, and the townies pass by sometimes they will wave at each other etc. Ok, that's normal, but what caught my attention was when some of the men and female townies began flirting with each other autonomously, charming, etc. on my sims front lawns, and it was being accepted. I selected them to check their relationship scores and some of them are at friend status with each other and a few have developed crushes. They have no memories of meeting each other, etc.
How can these townies be getting jumps in their relationship scores when I haven't even been to a community lot where they would be allowed to mingle with each other? Does the game automatically create townie relationships or is there a secret place that the townies go to that I don't know about?

The only hacks I have in regards to relationships are the romancemod and norandomflirts. I did have 2Jeff's casual romance (the old one) but I took that out before creating this hood.

[Ancient Sim]

The game does it automatically.  All townies & downtownies are given friendships with a small selection of other townies (the number varies) at random.  I think it's so that when your newly-moved in Sims get their 6pm invite downtown, the townie who invites them has some other friends to bring along.  If you don't want them to have these friendships, remove them in SimPE.

[PlayLives]

Oh wow, I didn't know that, thanks Ancient.