Transporting several millions of people yearly and cheaply(these people don't pay for extra leg room) is not really rocket science.
Right now it's so expensive because the government is as always disconnected from reality. They are deporting each individual on case by case basis using. air flights. The gov is even allocating one or two officers for each immigrant. Now consider boarding all the illegal immigrants on a big livestock carrier. It may take a while to reach its destination(s) but it will be cheap and surely the immigrants(at least most of them) would not try again the adventure. One big immigration camp in a single trip.
Where have I seen this before? Ah yes, trans-atlantic slave trade.
Because some white men drew them on maps....
Sykes-Picot was a disaster for the middle east.
You dont know anything about slavery today.
Your beloved private sector literally sells slaves to construction companies in Dubai.
The only complains I've heard are that you can't get citizenship. What I like most is that people doing "funny" business are quickly deported. You don't see homeless people or beggers on the streets either.
I wonder, why Europe can't do that? I don't think there would be much push-back against migrants if we would have an efficient deportation system(i.e deport them after visa expiration or when they get involved in criminal activities).