A group of about 7,000 people from China visited southern California in late May, their one-week stay in the US setting a record not only because of the unprecedented number of individuals in a single group, but also because of the economic benefit — $85 million — it generated for the city of Anaheim, Orange County and beyond.

Despite the high level of exposure of the group and their many shopping purchases, they left the US amid controversy, complaints, and criticism, mostly on account of their behavior.

Starting May 21, members of Perfect China, a direct marketing company that sells health food, household and beauty products, took 86 flights to come to the US, stayed in 26 hotels and filled 13,000 to 14,000 hotel rooms. According to Union Pay, each member of the group spent $10,000 or more during the visit.

"We are making history," said Xu Guowei, vice-chairman of Perfect China.

They were also making a bad impression. Describing some members of the Perfect China group as pushy, loud, intrusive and unruly, chartered bus driver Eric said they blocked the disabled access in Sea World in San Diego to take group photos and argued that it was their right to do whatever they wanted.

In casinos in Las Vegas, members of the group spit on carpets and ordered numerous refills of drinks without tipping waiters or waitresses. Female members of the group occupied the men's rooms in the lobby, leaving men waiting in line, because they didn't feel like walking to upper floors.

Jimmy Liu, a tour guide in Los Angles, said there is a lack of knowledge about American culture, tradition, regulations and social norms. "Some of the members brought their habitual bad manners, spitting for example, to the US and left unfavorable impressions here," Liu said.

Each year the number of Chinese visitors to California has been increasing, said Caroline Beteta, CEO of Visit California, which helped bring the group over. Beteta said her agency expects a 63 percent growth in Chinese visitors between 2013-16, and estimates they will spend $2.2 billion in California on shopping, lodging, dining and transportation.

In 2013, more than 1.8 million Chinese visited the US, a 23 percent increase over the previous year, and they spent about $9.8 billion, said Yuan Nansheng, consul general at the Chinese consulate general in San Francisco.

In 2000, the number of Chinese travelers reported an exponential growth as 10 million made overseas trips. In 2008, more nations, including the US, signed agreements with China to allow tour groups, a move helped bring in more Chinese tourists. In 2013, Chinese travelers became the single largest per capita spending group in California, the No 1 American destination for Chinese tourists.

As China rises to the second largest economy in the world, Chinese visitors are also sweeping everywhere including Europe, Australia, Southeast Asia and Latin America.

Although destination countries and regions welcome the tourism dollars and the buying power, they are upset with the chaos, hassles and bad behavior some Chinese tourists bring upon their cities.

In light of the Chinese tourism boom, some industry insiders believe the government should implement educational programs. For example, mandatory etiquette classes for visitors prior to their departures are encouraged to help them better behave in foreign countries and cultures.

"For instance, Chinese should get familiar with table manners, know concepts such as personal space, privacy and waiting for your turn," said Shino Wang, reception manager with a five-star hotel in San Francisco. "The more they are exposed to these Western norms, the more appropriately they will behave."