Go to Singapore and see how the immigrant laborers from South Asia live, how the native Malays live, and then how the ethnic Chinese and Western expats live. It's a highly stratified society where money makes the rules.
Have you seen how the poor 'native Malays', poor 'ethnic Chinese', poor 'ethnic Indians' and 'lower class Western expats' live... side-by-side, in rather bad neighbourhoods (which would seem spectacular in most Western countries)?
Yes, i do realize there are vast differences between immigration in the UK (or the west overall) and Singapore, but find that blaming class differences and/or the mistreatment of poor immigrants to policies is to simplify the issue.
No, Singapore's approach is fundamentally different. Singapore does not tolerate "poor immigrants": instead, it imports a vast menial labor class, who are tied to their employers on fixed-length contracts that amount to somewhere between indentured servitude and slavery.