The biggest question is how long have those items been on sale on eBay. In the US's version, there is only one used i3-6100 for sale and he's asking $92.99USD and it only has one day remaining on the listing. The rest that I can see are sold new in the box or new OEM.
Regarding the GTX 760 2GB video card, there are dozens of them for sale, most around $100USD. And none of them are even being bidded on. In short, people are not buying used GTX 760s.