It has now been made obvious that the main aim of the ship Doulos entering ports is not the selling of books but the conversion of people to Evangelical Christianity.
It is of course free to do so and people are free to adhere to any faith. However, it should be clear to Catholics that Evangelical Christianity has many tenets that go directly against the teachings of the Catholic Church and more often than not is hostile to them.
This is especially true regarding the sacraments, especially the Holy Eucharist, fidelity to the Pope and the veneration towards the Mother of Christ and the saints. Evangelical Christians are very active in Central and South America and this has resulted in millions of Catholics leaving the Church and joining the countless evangelical sects active in that continent.