Darwin's objection to Christianity

Darwin once wrote,

I can hardly see how anyone ought to wish Christianity to be true; for if so, the plain language of the text seems to show that the men who do not believe, and this would include my father, brother and almost all my best friends, will be everlastingly punished. And this is a damnable doctrine.

It would seem that Darwin could on the very same grounds express his displeasure with an amusement park owner failing to forcefully drag onto the premises of his establishment every single person who (on numerous occasions!) had received free admission tickets and had chosen to through them away. By a Darwinian leap of logic, such an amusement park would be so inherently abominable that its mere existence should be deemed utterly undesirable by all (apparently, even by the folks who are ready to show up at the gate with their complimentary admission tickets).