Yes, thousands of migrants are coming in to the EU both into Italy, Spain and France.
The biggest single 'volume movements' are probably the boats crossing the Med into southern Italy, reason why that is also where you get most news stories from. Not many migrants from Arab countries or Africa speaks Italian, reason why they transit through as quickly as possible. A good portion do though speak French, especially from the northern African countries, so those migrants tend to stay on the southern French coastline along the Meds. The attraction about UK is probably a combination of several things, such as they do understand/speak the language already and the idea (fact?) that its easier to find a job to earn a living. Mind you, the unemployment rate in Italy and France and especially in Spain are very high. And communication from succeeding migrants back to their friends and families are bound to be spread eagerly in the community back home where they migrated from.
EDIT: Just found the numbers: Italy 13%, France 10%, Spain 26% and the UK 6% unemployment rate.
For the lorries, then yes, one would think it would be easier to lock them better. Cutters and other tools are though often being used by the migrants to force them open. No simple solution exist for such migration problem, but rest assured, the majority do not leave their home just for comfort reasons. Traumatic living conditions are typically at play, and the root cause of that needs solving before you will see a stop to migrants risking their all for the faint hope of a better life.