Here are some of the reasons
1. America dropped the A-bombs on the civilians in Japan. You Americans are taught in your schools that it was inevitable. It is not true. You could avoid it if you explained what bomb you had and what consequences it will have on humans. You did not use deplomacy. You never do. Your government dropped them to test the bombs on humans. Period.
2. You supported all bloody dictators around the world including Saddam Hussein, (for example Haiti). You won't find this info in your textbooks. Do some research.
3. Vietnam
4. Iraq. You turned the country into the civil war disaster. Millions were killed and humiliated.
5. Iran. No evidence that they will use the technolgy to build the nuclear bombs. Same lie as with Iraq. You lie to your own people and the world. Only God knows what other countries you are planning to attack afterwords and for what reasons.
6. Support Dalai Lama and other separatist movements leaders. This lead to civil wars and many deaths in many countries.
7. You kill civilians in Afghanistan. You have no compassion. Looks like you hate everybody exept yourselves
8. Intervening with internal affairs of independent countries forcing them to do what YOU want. Not what people of those countries want.
Example, Ebargo on Cuba since 1958. You turned many Cubans into poverty. Thanks to God they still live better than many other people of Latin America for example Haiti, Jamaca, Dominica etc. But they could live much better if there was no embargo.
This is not all. I have no time to write it all. As you can see it has nothing to do with gealousy. And the word hate is not not the right word. People don't like Americans. Hope it helps.
As for that you live better than people in other countries. Even in Mexico your neighbour some people live better than many Americans. Only poor and uneducated people want to go to live in the US because as workers they get very little in their home countries. Plus the difference between the dollar and peso play its role. Many Americans are poorer (and are in debt to their ears) than many other people in other countries, homeless and jobless and many have no money to cure their teeth.