Are zoom in/out buttons necessary anymore?

Zoom buttons still exist in almost all desktop applications as well as applications on the web (SAAS). It seems like these buttons would be gone by now (with pinch and mouse scroll wheel) but they are not. Why do UX designers still keep these buttons around? Are there any good articles on this?

I found some UX stackoverflow posts on zoom buttons, but not one really stated whether or not they thought it would be safe (accepted by users or even noticed) if the zoom buttons no longer existed.