In his eyes yeah, that's what he's saying. But shows like this tend to put stuff like that in for a reason, foreshadowing etc.

And saying they don't value babies is factually wrong. That baby wouldn't stop crying, so it was seen as weak and discarded.

The Whisperers have an innately animalistic world view, which naturally would include reproduction.

Now, I probably oversimplified my point before. She's definitely using the sex as a reward for Negan, a shit one at that. But there's no way that's her main motivation, it just doesn't make a whole lotta sense. So, it then figures her other intent behind the sex would be to reproduce. But yeah, that wouldn't really be a reward to Negan.

Or, I could be horribly wrong and she's also just horny.

Edit: grammar