For a long while, my home laptop was a Chromebook Pixel. It had touch and a retina-quality screen when both those things were novel.
I found the touch useful for momentary interactions, like buttons. It's quicker and easier to reach up and hit NEXT than it is to find the cursor, move it to the button, and click.
Definitely don't use it nearly as much as on a phone, but it is useful for surfing.
I had the same experience. You need both the trackpad and the touchscreen they are complementary and great for different use cases. I've always thought chromebook pixel was a product ahead of its time, and time is confirming it seeing how many later laptops (specially apple) has ended up adopting many of its features.