[Margaret Pilkington]

No you are not missing anything.
Much as I feel for these people(it must be very difficult to pick up sticks and travel in appalling conditions to a country whose language you have no grasp of).....BUT, you are right legal or illegal, they are the responsibility of the country where they first make landfall.
This situation will not be cured by European countries accepting them and assimilating them...it will only be cured by stopping those who are exploiting these migrants and stopping the migrants from taking to the boats.

These migrants do not want to stay in either France or Italy because they do not have the same approach to doling out welfare that the UK does.......these migrants are attracted to the idea that they will be housed and given money and health care in the UK.
Maybe that is what the Mayor of Calais is alluding to.