That white collar supervisor is part of the proletarian. They are selling their labor to make a living.
You're right about stratification of society based on income when it comes to us proles though. Some of us have nicer toys and living places but we still need to work to survive unlike the bourgeois that make their money by capital investment (ie: they make more money with the money they have and don't actually need to labor).
Yeah I hear you I'm just saying those dudes are part of the proles and you need necessary to buy in from them in an organization for anything to really change.