Consider these different expressions:
Alcoholic drinks will be served [to people] by waiters at business receptions.
People will be served alcoholic drinks by waiters at business receptions.
The sentences above say pretty much the same thing. As you can see, the drinks can be served to people, or people can be served the drinks. In the first sentence, the phrase "to people" can be safely assumed (unless it's a party for dogs), so it is common to omit the phrase. This first sentence is an example of a sentence containing an intransitive verb. The second sentence has a direct object of "alcoholic drinks," and so will be served is an example of a transitive verb.
The second example can be re-stated like this:
All humanity would be served by a tiny handful of people... even if the tiny handful had to suffer for it.
In this sentence, the verb is once again intransitive. It is a way of saying that all of humanity could benefit from the suffering of a small number of people.