You mean the culture that they learned mostly on the streets of Los Angeles before the US exported their violent gang problem into Middle America?
And you do know that they are present in:
The San Francisco Bay Area in California; the Washington, D.C. metropolitan areas of Fairfax County, Virginia, Montgomery County, Maryland, and Prince George's County, Maryland; Queens, New York; Long Island, New York; Newark, New Jersey, Plainfield, New Jersey; Jersey City, New Jersey; Elizabeth, New Jersey; the Boston, Massachusetts area; Charlotte, North Carolina; and Houston, Texas. There is also a presence of MS-13 in Toronto, Ontario, Canada.
So sadly these inhuman bastards are found in much more areas than Los Angeles.