second hand computer purchases

I was looking to buy an upgrade cpu for my dated pentium 4 desktop machine. The one I would only give money to since the machine is so old, was the sl7ch. Which used to be the flagship of the P4 range. Looking in Ebay and elsewhere this cpu commanded prices exceeding 200$.
Now I sit and think. Who in their right minds would give so much money for a single old cpu since with the same amount one can buy motherboard, memory and modern cpu with double and triple even quadruple the power of this old P4.
The answer is of course nobody. Which a remote chance that some "collector" would shed all this cash to acquire this old gem. But even that chance is pretty slim.
Even the small brother of sl7ch the sl7aa commands a minimum price of 50£ on Ebay which is freaking crazy considering that the same money can buy a brand new dual core cpu.

So in my search to upgrade my date PC I ended up considering a 200€ expense getting a motherboard, memory, cpu, power supply and cooler while keeping my hard disks, keyboard-mouse, screen, DVD writers and tower.
Why the f@ck pay real money for overrated products anyway in the current economy?

Similar observations stand for other computer equipment such as batteries. I came to own a mobilepro 900 first introduced in 2003 and upgraded in 2004 as 900c. However the battery was half dead. Looking around, I found in Egay an extended battery costing 170$. More than twice than I paid for the 900c and shipping! and I ended up exchanging the battery cells on my own as seen in previous post. I wonder does the company realise that nobody will give so much money for such a dated product? I understand that they probably cannot sell it in lower price than they acquired it for, but still having it in the storage aging and gathering dust, how is it better than selling it even for half or lower price?

The Nec 900 on itself although a great little machine, has been so outdated that has serious issues just connecting to the home network (no WPA or WPA2 support), not to mention lack of support of Flash and other protocols that make it more or less unusable for web-surfing and since development and support of that windows platform has ceased, its up to hobbyists to keep it alive and update it if possible. So why the heck pay 100£ for a new battery when you can spend this money and get a wifi Android Cell phone with more capabilities and modern sofware?

I will be damned if i ever understood how marketeers and sales representatives really work.