why are people risking their lives to get here and leaving France which incidentally should be ashamed of how they have treated them.
That is correct, the French are ashamed but they also short of ideas what to do with thousands of people who have fled war zones to rejoin family in the UK. You really haven't been listening have you, they have been say the "why" all this time, I'll repeat: Most of them have family members already in the UK. The others speak (some) English not French so they think they will have a better chance of making a new start in the UK.
Remember thanks to the Touquet agreement the UK border is in Calais not in Kent so in theory it is the UK's slow treatment of immigration requests which is responsible, not the French authorities. For the moment these people have been bussed of to warmer more comfortable spots for the winter. Maybe they will learn French (they all speak English, or are trying)? Maybe they will take a liking to the spots where they are being put up and stay there? Maybe they will continue to try and rejoin their family already in the UK?
Then there is the Paris situation:
Would London be able to cope better with thousands of homeless and totally disorientated people living in tents under a motorway? Great! Come on then take them in and show us your superior organisation skills, after all it was you who started most of the wars they are fleeing in the first place.