One of those I know on Ebay does sell tat. She makes stuff and flogs it. Another one turned his obsession with classic cars into a "Find and flog you" spares for classics. He haunts these classic car rallies buying up old badges, door handles, bumpers .... all the bits and pieces and then advertises them on Ebay. Sends out up to 20 parcels a day. Has given up work to do it full time. Has wife and two kids. Just booked an expensive holiday for them all. He has been doing this for three years now, says it was tough to start with but now as many people contact him to flog bits off of ""breakers" as want to buy. He just sits in the middle and makes a profit. The third just taps the side of his nose and winks when you ask what he flogs.
It seems to work.