It's not necessarily easier to lose weight through diet than exercise, but good nutrition is an essential component of permanent fat loss.
In other words, you can't work out a bad diet. You can spend hours working out and never lose a pound of fat, if your diet consists of packaged processed junk in excess of the calories that your body uses. Remember also that you can consume too much of a good thing. It's all energy and that excess energy will be stored (usually as fat), if not burned.
However if you incorporate a good balance of strength training, cardiovascular exercise, some type of flexibility work like stretching or yoga, meditation or some kind of stress relief and a good balanced whole foods diet that also includes a slight daily caloric deficit. The results will remove and keep excess pounds of fat coming off.