Midlifeflyer is right on the $$. The DP's are there for your safety as everyone has stated and it is imperative that you fly them in IMC conditions. They are however negated if tower gives you a turn other than the DP. If tower has you in radar contact and gives you a turn you are supposed to follow that. I believe in NOS charts there is a dedicated section but we use Jepps so I'm not sure. Other than this what everyone else has said is right on the mark. Our company requires us to brief any DP's for the RWY we use prior to all T/O's regardless of IMC vs. VMC. I think they were originally for non-towered airports but they are at all now if the airport needs it. They are there for any obstructions, not just terrain above x height and within x miles of the rwy and again can be referenced by your A/C climb performance. I believe SAV has some for towers and stacks. Flame away.