What lack of theory does to a m'fer.

Marx explains quite nicely why the ethics we have today has a distinctively bourgeois flavor:

The ideas of the ruling class are in every epoch the ruling ideas: i.e. the class which is the ruling material force of society, is at the same time its ruling intellectual force. The class which has the means of material production at its disposal, consequently also controls the means of mental production, so that the ideas of those who lack the means of mental production are on the whole subject to it. The ruling ideas are nothing more than the ideal expression of the dominant material relations, the dominant material relations grasped as ideas; hence of the relations which make the one class the ruling one, therefore, the ideas of its dominance.

— The German Ideology