Perhaps all the lazy Brits will have to do all these jobs?
Although it is unlikely all the EU nationals here will be frog marched out there comes a point when they naturally move on to better things leaving a gap in the employment market for an indigenous member of the benefits society or young person just starting out to jump in.
As an aside but related topic, I did always wonder if those clamouring for 'Johnie foreigner go home' would be willing to take up the often menial work they left behind. As I said it might help get people off benefits!!