Arcanine IVs

Support arcanine with snarl and flare blitz should have all best in 6 IVs right? Can somebody explain why they run 0 SpA IVs if snarl is being used? I don't really get it

Arcanine @ Mago Berry  
Ability: Intimidate  
Level: 50  
EVs: 244 HP / 44 Def / 220 Spe  
Jolly Nature  
IVs: 0 SpA  
– Flare Blitz  
– Snarl  
– Will-O-Wisp  
– Protect