The answer is that migrating people do not have tickets they just pay with money, my opinion is that they work a lot to get lots of money and then they pay to get on the boat with the money they worked for. For one person It can cost like $1,000 or $779 which could corespond to one year of salary. For one family each person must pay $3,000. Now some countries ( in Europe ) try to open the doors to migrating people because one day recently they found this Syrian little boy dead on the sand. Om a beach in turkey. A lot of people raised their voiced for that.
(That is him . On a beach dead .)
(Where I found the information about the boy : I found it on TheGuardian )
( where I found the information about no TIKET and stuff : on the economist)