There are no Hispanics in Latin America.

Hispanic is a US term.  Only when they arrive to this country, all the people from Latin American and Spanish heritage fall under the Hispanic classification, despite their differences.  

US Hispanics share a common language due to ancestral ties to Spain, but US Hispanics are highly diverse. In the United States, Hispanics are both an indigenous and an immigrant community. 

Many are recent immigrants; but many have been here for more than one generation and even represent families that date back to the first Spanish settlements from the fourteenth century in what is now the United States, antedating by over a century the creation of a permanent English colony in North America.  

US Hispanics represent 20 Spanish-speaking nationalities; They are Colombian, Venezuelan, Mexican, Cuban, Argentinean, Hispanic Americans etc. and have lived through complex cultural, social, political, demographic, and economic patterns. 

This means differences by generation, legal status,  nationality and culture.  

There are also significant differences in vocabulary between regional varieties of Spanish, particularly in areas such as food products, everyday objects and clothes, and many Latin American varieties show considerable influence from Native American languages.

Advertisers face a significant challenge. And the discussion about the US-Hispanic advertising finding its own identity is still going on.

The US is the second largest Spanish-speaking region in the world. Currently, more Hispanics reside in the United States and its territories than  the population of Colombia — the largest Spanish-speaking country in South America — or in Spain itself. Only Mexico, with a population exceeding 100 million, has a larger Spanish-speaking population than the United States.