Excuse, but I thought it was about ILlegal immigrants, not your average everyday immigrant.
Sure, at face value it is illegal immigrants. But the first step to controlling this is to make it incredibly difficult for people to enter the country for even tourism purposes. Which has been done in the USA. People from any European country have to apply to a special website weeks before travelling to the USA. It is currently very annoying for most people to travel to the US, for instance.
Your typical illegal immigrant will usually enter the country legally, but will work or remain there illegally. Those people that want to stamp this out generally view all immigrants with suspicion. In any case it breeds this distrust.
So no, not just illegal immigrants.
The fascination with illegal immigrants is indicative of a poor view of immigration at large.