What's the scope of illegal immigration in the UK in comparison to the US? Let's look, shall we?
UK:
Estimated between 310,000 and 570,000. Total UK population? 63.23 million - a little less than a percent at the high end of the estimate.
US:
Estimated 11.5 million illegals, total population 313.9 million, or about 3.6%.
Now I'm guessing that if you took the UK and set it down between Romania and Bulgaria, those UK stats would change quite a bit. Being land locked next to a third world country has a bit to do with it. So you can't really compare the UK and the US. At all.
There's a whole process that immigrants can go through in order to gain citizenship - the right way - that allows them to gain the opportunities, the chance of a better quality of life, etc. In fact, decades and decades ago, that's how it worked- before they got schooling, welfare, food stamps, medical care, housing, etc. And back then they contributed in the form of taxes.
Now, all we have is a population content to remain under the radar and not contribute a penny towards what they receive, with no intention of becoming legal. Why? Because they don't have to. Why sign up just for the right to pay taxes when you already get all the freebies as it is? Hell, if you want to vote, you probably could still do that!
What's the absolute worst that can happen to you? Catch and release? We're not going to deport you or anything, right?
As for swapping productive immigrants for lazy citizens, where can I vote on that program? It's a keeper.