The Torah looked after the Leviim, who were generally very poor. The Kohanim did not receive a portion of land as was the case of the Leviim, but they did receive twenty four special gifts.
We are told that there were a total of forty eight cities of refuge scattered all over Israel. Every city in Israel had a rule that they were to measure 2000 אמות (cubits) outside of the city limits. The first 1000 אמות were to be left empty, to add to the beauty of the city. The second thousand אמות was given to the Leviim which they could use for planting.
The Leviim also received מעשר ראשון from the entire nation. So although they did not achieve great wealth, the Torah did provide the Leviim with a source of sustenance.