This is a large part of why eBay favours the buyer[†]. Yes, they need sellers, but if you stop selling the buyers don't go away so someone else will take your position in their market (no change for eBay overall) or increased competition will increase prices (so eBay make the same despite lower sales due to % of sale based fees).
People buying from sellers using eBay as a platform are the more treasured resource, much the same as the people reading from publishers who are using facebook as a platform, and the same dynamic exists in many other places. Only when a resource is truly both in specific demand and scarce does this situation reverse.
[†] or at least it feels that way to most sellers, buyers still sometimes feel shafted too though that are shafted less than sellers.
People think I need this or feel entitled to my attention? o my?
As others have said, it is insanity to invest time and money into a business that is partly controlled by somebody that you have exactly zero control over. Same as having a single supplier or a single customer.