People who are comparing this video to Venezuela today, or of American corporations, are totally missing the point. That's really close to what it was like. Thousands of Americans lived in Venezuela in the 1950's and 1960's can testify to this. (I came a little later and lived there for over 20 years.) This film was made at a time when many Americans were going to college, often for the first time in the lives of their families. To them, a very high-paying job, generous benefits, and a sense of adventure were worth the minor inconvenience of living in a Quonset hut for a few years.
The country was not a democracy, but it was economically stable, with little crime, very little anti-American sentiment, no drug problem, and no tradition of violent political unrest. The Perez Jimenez government welcomed foreign investment and was spending a lot of money on things like schools, hospitals, roads, etc. and living standards were improving a great deal during this era. When he was overthrown in 1958, the transition was very peaceful, compared to many countries before and since.
There are hundreds of natural oil seepages in and around Lake Maracaibo which brought the international oil industry there in the first place. The lake is polluted now, but mostly due to untreated sewage treatment from more than 2 million people who live around it, not the oil industry.
P.S. The Spanish is just fine. The Venezuelans shown are speaking slowly and clearly for the camera. And no, they don't sound like Mexicans, Spaniards, or Argentinians.