Good point which leads to another question. What about unwinding an operation such as this? There is income tax to pay, Social Security tax to pay, state income taxes to pay, multiple state sales taxes to pay and on and on. Even one person traveling around doing something such as this runs across a plethora of permits and regulations. Sometimes bonds are required.
And these people simply were told to leave and no one is interested in seeing they obeyed various state, local and Federal tax and other laws? That makes no sense.
Since they weren't US citizens these rules need not apply. Just ask any Mexican national working in the US. The fact that the Israelis actually got deported (when was the last time you saw a bunch of illegal alien Mexican gardeners sent packing) tells you that something more was going on.