... for the same reasons you've cited. For example, a lot of the undercarriage work on my tundra requires removal of the skid plate. While the haynes book shows where the bolt locations are, it was pretty useful watching someone going through the motions, if only so get an idea of if I really should be under the thing when unlatching it. :D
I went and picked up the haynes manual for my truck anyway, primarily because the shade tree mechanics tend not to include things like the torque values for minor unimportant things like the oil pan drain plug or oil filter cover.