All good questions. I've bought my fair share of second-hand tools and stuff from HF, and decided that after all the research I did and long-term plans I have, so I ended up deciding this purchase was the best one for me to make. But you said it yourself, "why spend that much?" Simple answer, I now only want quality tools in my shop. I mainly use Hitachi and Dewalt tools at this point, but still have some old black & decker as well as some craftsman stuff that I bought years ago when I first got into woodworking.
It's like my kayaking & guitar playing hobbies, I started out with less than high-end equipment and as my skills and talents got better, so did my equipment. I went from a crappy $100 kayak to owning 1 $1100 perception kayak & 1 $800 wilderness systems kayak. The difference is significant and I thoroughly enjoy getting out on the water on these two boats whenever I can. When I started playing guitar when I was 14 years old, I had a decent Washburn acoustic guitar that I learned on, but as I got better, the washburn just didn't have the sound or playability that I desired. 24 years later, I have a Taylor, 2 Takamines, and a few others that do.
If I'm going to invest in improving upon a hobby that I really enjoy, I'm going to go ahead and invest in quality equipment (not saying you can't get that on CL from time to time.) Hope that answers your inquiry.