Yes and no, they straddle the class division just like the Labour Aristocracy. They are similar to the haute (high) bourgeoisie in their social reproduction, which is derived from extracting surplus value off of the proletariat. So if you apply a moralistic perspective to Marxism, they too are “vampires” who survive by exploiting others.

However, unlike the haute bourgeoisie they still control very little capital. This means their economic power can sustain them, but does little for their political power. Besides, in many cases petite bourgeois families that own small enterprises still have to work themselves in those enterprises. They are also much more like the proletariat in how vulnerable they are to crises and political violence, being too just a stone’s throw away from poverty and wage labour, whereas bankruptcy for the haute bourgeoisie means only a temporary embarrassment.

So the petite bourgeoisie for the has their long term strategic interests more aligned with the proletariat, with regards to wealth redistribution, combatting poverty, public services, etc. but they tend to be more tactically aligned in the short term with the maintenance of capitalist relations, as they derive their very immediate survival from it.

This is why Mao saw the petite bourgeoisie (among other classes) as allies of the proletariat in the revolution, because they’d also benefit in the long term and were very useful but were not fit to lead the revolution.

But to answer your analogy question, it’s more like a pyramid. Even well paid proles benefit from capitalist relations wrt their lower counterparts, and the petite bourgeoisie is not even necessarily entirely above all of the labour aristocracy. But it’s way more likely that a small business owner who owns, for instance, a bakery or a pub could go bankrupt and become a wage worker than that he could become a billionaire. To believe otherwise is to fall for liberal ideology.