The issue with chocolate is theobromine. Carob contains theobromine but in much smaller quantities (somewhere similar or lower than white chocolate). So a dog would have to ingest a large quantity to have a problem. I see carob on hand baked dog treats at local pet boutiques. Based on that, I think probably a small amount infrequently wouldn't be a problem.
For me personally though, I probably wouldn't give it to MY dogs…that is just me.