It's an ideal, something to strive for.
Having money is a benefit when navigating the legal world. It doesn't mean that those with money have an advantage, it means they aren't as dis-advantaged. After all, the government has more resources than any rich guy.
She's not blindfolded on the top of the courthouse in my hometown either. Apparently this isn't uncommon...From Wikipedia:
Lady Justice is often depicted wearing a blindfold. This is done in order to indicate that justice is (or should be) meted out objectively, without fear or favor, regardless of identity, money, power, or weakness: blind justice and blindimpartiality. The earliest Roman coins depicted Justitia with the sword in one hand and the scale in the other, but with her eyes uncovered. Justitia was only commonly represented as "blind" since about the end of the fifteenth century. The first known representation of blind Justice is Hans Gieng's 1543 statue on the Gerechtigkeitsbrunnen (Fountain of Justice) in Berne.
The blindfold raises some common questions:
Do you want to blindfold someone with a sword?....And how is she supposed to read the scales if she is blind? This troubled early representers of Justice; some thus gave her two faces like Janus, with the side bearing the sword prudently left unblindfolded.
Instead of using the Janus approach, many sculptures simply leave out the blindfold altogether. For example, atop the Old Bailey courthouse in London, a statue of Lady Justice stands without a blindfold; the courthouse brochures explain that this is because Lady Justice was originally not blindfolded, and because her “maidenly form” is supposed to guarantee her impartiality which renders the blindfold redundant.