I have a friend who only buys fabric for her current project. In some ways I envy her until I get a little down and make the time to just go downstairs and look through my little fabric friends. I try to justify it to my husband my reminding him how much more expensive it would be to have me go to a human for help (or drink heavily for that matter) He just rolls his eyes.
The other thing is that since I go out looking for bargins often, I do not have as much inevested in each project as she does.