I think that some chassidim have a different view of marriage than most people. My wife had conversations with a few chassidic women while in the hospital during her pregnancy (it was very complicated, and she was hospitalized towards the end of it).
The women told her straight out that the sole purpose of marriage is to have children. One woman asked her, “What else is there?” If you go into marriage with an attitude like that, then a B’Show is fine. Who cares if you really like each other? As long as you don’t hate each other, you’ll be fine. Just have kids, and that’s all. Do you love your spouse? It doesn’t matter, just have kids.
If you don’t view marriage like that, dating is important. If a marriage is about two people living in harmony together, building a life together, and not just being about children, then they need to be sure they are able to grow together. They need to complement each other. Dating is better for determining that.