This was the extreme end of the supply chain so to speak. Iceland was sparsely populated, Greenland even more so. They simply didn't have the people to set up n

This was the extreme end of the supply chain so to speak. Iceland was sparsely populated, Greenland even more so. They simply didn't have the people to set up new colonies further west, or much need to. Perhaps, if they had stumbled on a particularly rich area, they may have done so, but to get any significant number of settlers, they would have had to go all the way back to Scandinavia.