You also have to consider the reality that these groups are weak militarily within their own regions, that is why they struggle to carry the battle to Russian militia and army forces.
Apart from an attack on a police station earlier in the year Ingushetia's been fairly quiet, suicide bombers are just crude guided missiles, militarily it is just a way to go boom.
The effect of this is political rather than strategic, it serves to remind the people that the opponents are still there, even if there's only twenty of them, they can still make an impact.