Argentinian currency regulation might be very relevant issue with this case besides revenue management. I'm not totally up to date with current regulation but I imagine that for foreing carriers it's much harder to exchange Argentinian pesos to USD using official rates than dealing with local currency even in Bolivia. Isn't the difference between blue and official rate something like 30%?

Another issue is local VAT (=IVA/IGV) regulation. For instance, one doesn't have to pay VAT when buying international flights originating from Europe but local VAT is charged when originating from Peru, Ecuador, Colombia etc. After taking into account these factors, the difference suddenly is much smaller...