They eat maize instead.

Look at all the food in Mexico, Colombia, Venezuela, Peru and Central America. It is made with maize flour instead of wheat. The amerindian tribes already used maize as flour to cook stuff before the Europeans came, so the wheat was not needed.

Only in Uruguay and Argentina we use wheat mostly instead because we are the countries with the least amerindian influence as most amerindian tribes were exterminated through genocide (it's not like there were much of them living there anyway). Uruguay has high black/mulatto population (10%) but little to no amerindians and mestizos and most of the population is of European descent, even the so-called "blacks" have some European admixture like Luis Suarez.