This list is not really up to date. Megacoin, Quark, Worldcoin are in the top ten by market share for weeks. Terracoin is dying and still under established. Quark is not even under candidates

That's because Quark is a piece of shit scamcoin with 97% of all coins already mined. the "top ten by market share" doesn't really apply here.
No it isn't a scamcoin for me and for many people neither. So it does not count, what the market says but some self-appointed judges? Who decides what a scamcoin is? I like Quark. 30sec + CPU mining + different approach for distribution.
60-70% of all Bitcoins can only be minted by professionals (FPGA and ASIC) and the rest by high risk early adopters. With Quark nearly 90% get mined by high risk early adopters. What is more fair? Bitcoin's distribution? Ok, that is your opinion and there are many valid arguments. But please don't see another distribution as scam!