Why did the early believers meet in their own little fellowship groups?
The early believers met in their own little fellowship groups because they were now separated from the mainstream of Judaism, so those groups were the only place they could really talk together. There they devoted themselves to the Apostle's Doctrine, fellowship, breaking of bread, and prayer, and shared meals together.
Les teaches that these believers had been separated from the mainstream of Judaism, so the only place they could really talk together was in their own little groups of fellowship. In Acts 2, they continued in the Apostle's Doctrine, fellowship, breaking of bread, and prayer. Les points out that this was all very normal and common. He also notes they had their meals together, and he often illustrates that you can know someone casually for a long time without truly knowing them or their family until they invite you into their home for a meal.