I have yet to meet a single Mech Lock in Wild. Should I consider myself lucky?
What rank are you? I don't see them either, but I hover around 15 using pretty janky/fun decks - according to TempoStorm it's the only S-rank deck they've seen in a long time (or ever; I can't remember exactly what they said).
As for Snip-Snap as a whole, he only seems broken if you reduce the cost - so that's the real issue here (I use him in basically all my highlander decks; he's a good 3/6/9 drop without any combos and he synergises with N'Zoth). If you made him cost at least 1 even when comboing off, that would likely be enough - I think you'd get 7 off at most, baring the coin and/or Emperor shenanigans (which are going to take more RNG or time to set up).
I wonder too.
I have met a single other warlock (!) between 10 and 5 this and the previous season.
Snip is fine though. Mana cheating is the thing that needs to be adressed. Not only in this case.