Hey, I thinks that depends on level of details you require.
First, please take a look at (as far as I remember) this sci. paper: http://graphics.pixar.com/library/AnyoneCanCook/paper.pdf
There was a description of modeling pile of trash. On the final image you see low poly textured base with some modeled 3d details on top of it (roughly speaking - without going into unnecessary in this case details, like shaping the pile and the simulation)
If I were to model some tidy laying towels or hanging on the hook, I'd definitely do this by hand. If I were to model pile of random trash I'd try the Pixar's way.
1. Might look too fake and detached, and imagine bending and placing all clothes by hand...
2. Simulation of all clothes will take really lots of time, unless you simulate only 2-3 pieces of clothing on top of the fake base pile.
3. Why not to build basic meshes (just general shape) in Anim8or and then sculpt it in Sculptris according to photo reference? Then decimate resulting mesh a little bit in MeshLab?