Because you never stand up and do anything about it.
Has anyone been out in the streets protesting rhcusa.com, USIN-PAC, or NASSCOM?
Or protesting the Title 9-violating India Inc staffing firms opening shop all over the US?
Or in front of the Capitol in DC like the sob-story H-1B job robbers do?
Nope. Few Americans seen doing that.
If you don’t actually do anything about it, it will continue.