The reality is that we all live under a single currency, the Rand. A currency is both the oil which facilitates the transactions that build an economy and the string that binds the transactions together into one whole. The reality thus is that every bit of the economy effects every other bit whether we like it or not.
Political parties ignore this reality when they propose policies which will apparently economically benefit one bit of the economy at the expense of another bit, or bits. The damage that such policies do is not, and cannot be, limited to the directly effected bits of the economy, they negatively effect the whole economy. AA, BBEEE and EWC are such policies.