Dear Niantic, Increase wild Snorlax encounter rate
Same for Chansey.
Answers
I caught my first 3 in the Wild in September of 2016 in a Costco parking lot; I don't think it was a nest, but there were three there at one time and I caught them all because my wife told me how great they were. (I had only started playing the game maybe 2 weeks earlier, she started in July 2016)
Then I didn't see another in the wild until that Grass/Fire/Ground event in early 2018.
Snorlax and Chansey are supposed to be rare encounters in the wild, though (as others have mentioned) Chansey has been spawning much more frequently during this event. Same goes with Mons like Lapras, Aerodactyl, Miltank, Dratini, Larvitar, Beldum, Bagon, etc. They're not supposed to be common spawns; they're meant to provide that "woah!" factor when you do actually encounter one.
My suggestion is to play more frequently and in different areas, if you can. They're out there!
Snorlax spawns haven't been boosted for this event but maybe you don't realize exactly how huge the boost on Chansey spawns is. I've caught more than 20 this event without particularly hunting for them, which is more than I've ever seen in the wild before in total, both Valentine's events included. That's out of 120k catches. Chansey is an ultra rare, which makes it exciting to find one.
It's all "R"NG.
I've caught 10 Chansey in the Wild (and had a CP 1100ish!! non-weather boosted Chansey run on me after a single Great Throw with a Golden Razzberry and Ultra Ball. I actually screamed in rage when it ran.) since this event began. And 6 Lapras.
On the flip side, I have not seen a single Wild Snorlax in this event. Strangely, no Pinsir or Horsea either. But that's "R"NG for ya.