Didn't always work though, throw Kisame in Hidan and Kakuzu's team against the Leaf and you have fox for dinner.
Maybe not send ALL akatsuki but a increase from 2 to 3 so there's still some in the hideout or whatever, I doubt 3 akatsuki people going on a hunt would make the Raikage or whoever contact the other kages.
Look at what happen with Gaara. That was a team of 2 of them. Can you imagine what would've happened if the entire group had showed up and just destroyed the Sand Village. It would of just escalated the war. I mean if you look at the fact that the 3 Tails was roaming free so they had no issues there. To be honest with you here. If you read in the Manga since it isn't explained in the show. They sealed most of the tailed beasts pretty close together. They were gathering them about 2 at a time and then sealing them back to back. So by using 2 man teams that compliment each other they
A. Don't kill each other but enhance each other. Since most of them preferred to work alone when in their respected villages.
B. They cover more ground gathering more tailed beasts quicker.
C. They infiltrate a place and leave much quicker.
D. They cause less of a ripple when entering and leaving a city. (example- when Kisame and Itachi visited the Leaf Village to scope out Naruto)
E. They don't show their true full potential and play all their cards at once.
F. If one or both are taken down they don't lose more then 2 members at most to perform their Ritual to Seal the other beasts.
There are several more reasons though that the 2 man teams made more sense. I don't get why you are questioning this setup it makes sense on several levels since most of the jinchuuriki's are not even on the level that Naruto and Killer Bee are at so it made sense since they were able to move in and out quicker.
