I am familiar with the function of a lens hood, and I can understand that they could help to improve the contrast of pictures. However, I'm not convinced whether a lens hood does make all that much of a difference in practical use. I've read a number of online discussions on whether one should use or not use lens hoods. But as is typical of discussions on photography, there are lots of strong opinions, but few proofs.
I personally don't have the habit of using lens hoods, as it is simply a hassle to put them on the lens every time I take the camera out of the bag (and remove it again afterwards). I've done some quick-and-dirty tests with and without a lens hood in the past, and couldn't see a difference. Some similar tests can be found in this thread, that do show an obvious flare. However, in these cases, you will also see the flare when taking the picture, so you can put on the hood, manually shade the lens from the light source, or simply reframe.
But what about situations when there is no obvious flare? I'd like to see some objective tests of that case, preferably in controlled lighting. Will lens coatings make a difference, meaning newer lenses shouldn't need a hood as much as older lenses?