Over the years I lathered up Nivea Original many times without a brush. It used to be my travel cream and often didn't bring a brush with me. I also often took a Williams puck and rubbed it on my whiskers and worked up a lather with my hand.
I find I use less product by using a brush and I get better whisker softening with less effort because of it. So it`s always a brush for my shaves unless I forget to bring one along say during my travels.