The advantage of no-cook is the simplicity. It is quicker and less messy to make a no-cook meal. There can be some weight saving but not too much since you tend to carry food with higher water content.
For me, like others above, the value of a warm drink on a cold evening or frigid morning is worth the weight. I would find it a lot easier to switch to no-cook in warmer climates. Los Angeles (where I live) is certainly a warm climate but it gets cold in the evening particularly at the elevations I backpack at.