I disagree, do you really think they would kick out pensioners who are contributing to their economies , not taking up jobs that locals could do or social housing that locals could use ?
No. Like I said, I can't see EU citizens being kicked out of their homes - it's really, really unlikely. But, if that did happen and thousands of Spanish citizens came flooding back to Spain (and judging by the number of Spaniards in Brighton's Aldi, there are lot of them here), I can't see the Spanish government overjoyed by the cost of additional unemployment benefit to pay out.
So, yes, in the very unlikely event of mass repatriation of EU citizens, I would expect some sort of action from European governments.