As someone who's worn a full beard (inclusive, of course, of a moustache) for many years, wearing a moustache for Movember is never much of an issue for me.
However, not having one makes quite a vital difference to a number of famous faces, as the Mustaches Make a Difference campaign shows. This campaign not only promotes Movember, but also de-promotes a number of famous faces, from Gandhi and Einstein to Dali and Queen. The 'renamed' character sans moustache shows that this most remarkable facial feature makes a huge difference to the look of a man - it always intrigued me how many NZ policeman wore the 'police moustache' as I called it. It had a certain regulatory look about it, was very formal, and added an element of threat to the police face (note how ordinary Stalin looks without his moustache - it's the same process).
Here's just one example of these clever pictures: