even just the relentless emphasis on class and all the locutions: "the poor," "working people," "the middle class" etc. make people a bit squeamish as their own identities, so the direct address to "the middle class" doesn't directly engage many people. and the categories are indeed problematic in a thousand ways, though perhaps for some purposes indispensable. but that one would not immediately regard one's basic identity as fixed by one's economic role or place in a hierarchy is good, and bad too, i suppose. your basic leftist, still under the influence of marxism, regards appeal to every other sort of identity - religious or nationalist, or regional, for example - as red herrings, mere rightist propaganda, a disguise for capitalist interest. but these are as real in people's experience as their class. and there's no reason why they shouldn't be.