Knowing that Fighting type moves are super effective against Snorlax, we might choose them. But since Fighting type Pokemons have low HP, we might choose other type of Pokemons with Fighting moves.
However, is it true that, even though with Type Effectiveness considered, say, for a Rhydon:
Rock Smash DPS 10.6 x 1.25 = 13.25 (x 1.25 for type effectiveness) Mud Slap DPS 13.9 (with STAB)
So it really is not so useful to choose fast fighting moves to fight against Snorlax. I checked all 3 fast fighting moves: Karate Chop, Low Kick, and Rock Smash, and Rock Smash is already the most powerful of all 3. So in the case of Rhydon, it really is more effective to choose a Rhydon with Mud Slap than Rock Smash to fight against a Snorlax.
Actually, to have a good fighting charge move, we need Cross Chop (the other two fighting charge moves Brick Break and Low Sweep have low DPS). But for Cross Chop, it is only for: Primeape, Machamp, Machop, Machoke, Mankey, and Psyduck. So if we can't choose fighting type Pokemons due to low HP, and Psyduck has low HP and we can't choose it either, so we can really just forget about fighting type moves altogether?
Is the logic / reasoning mentioned above correct or is anything missing?