In “polished countries,” what made the lowest people rude and uncivil

From the text:

If, in polished countries, the lowest of the people are rude and uncivil, it is not merely because they are poor and ignorant, but that, being so, they are in daily contact with rich and enlightened men. The sight of their own hard lot and of their weakness, which is daily contrasted with the happiness and power of some of their fellow-creatures, excites in their hearts at the same time the sentiments of anger and of fear: the consciousness of their inferiority and of their dependence irritates while it humiliates them. This state of mind displays itself in their manners and language; they are at once insolent and servile.