'Locust' haters told to remember their roots

From the Standard:  'Locust' haters told to remember their roots

Hong Kongers remember their roots?  Their home is being invaded by Mainland Chinese who strain resources in housing, real estate, food, etc.  And they're fucking unappreciative of what Hong Kong has to offer them.  

I compare it to having an unwelcome unannounced guest that has overstayed their welcome.