I am sure there are some who don't like any kind of immigration; however, I believe most Americans are only concerned with illegal immigration, so it really doesn't do much to sway public opinion to claim that immigrants are good for the economy, since nobody is denying that and it is irrelevant to the issue of illegal immigration. Most people are fine with immigration, as long as immigrants come in legally. For example, my wife is an immigrant and currently holds a green card, but both of us are against illegal immigration. It's best not to conflate the two.