So, how do people in this modern world talk to people who believe that faith is a virtue?

I think one has to start by realising that there's a good deal more to religion that just 'faith'. To the religious person, what he believes in actually makes perfect sense. It's all too easy to see 'blind belief', when in fact there is an underlying rationale ( even if it is wrong ) behind much of religion.

Thus for a Christian, there's nothing irrational about observing that maybe people need 'saving'. Indeed, the more one argues that we live in a cold, heartless, indifferent universe......the more the Christian will argue that that merely exemplifies the point. The 'someone will get us out of this mess' sentiment covers most religion.....and even extends into all the new age stuff, with the gods being replaced by our 'space brothers' who are keeping an eye on us.

Once you expand the basis of religion like that, it's clear that there's more than just blind faith going on. Most people aren't so stupid as to just blindly believe things. They believe within an overall context and framework that has provided a storyline that at least makes some sort of sense to them. It is the story itself that needs questioning, rather than simply observing that the person is silly to believe in it.