Because I like them. You scientist worshippers are weird.
You get your undies all wadded up just because someone refuses to toe the "Science is infallible" line.
The fact that I'm sitting here typing on a keyboard and the words appear all across millions of people's monitors around the world does not make me believe that the oceans can be saved by spending 8 billion dollars just because some dead scientist's daughter says so.
Nor does it prove that life began as some random process initiated in a stagnant pool of water.
But back to the ocean thing. Do you believe the effects of global warming on the oceans can be fixed by spending 8 billion dollars?
Actually, I suspect that you use them because they work. And if the science behind it works, then you accept that bit of science, for use of a thing is acceptance of a thing.
Which reveals you to be a hypocrite. As it was you who stated, "Tell me again why so many people place so much faith in scientists?"
This at the same time you are putting your faith in scientists. Classic hypocrisy - "do as I say, not as I do".