The other exchanges that are in that list are also centralised. They support one or more BTS tokens, but they are also not DEX's in and of themselves. So, that is why I added MXC, WALLDEX, XBTS, etc. I am not sure what you disagree with...
I'm surprised that you didn't see the differences.
They are different types of "partnerships" to BitShares.
With XBTS, WALLDEX and etc, the users' major activities are on the BitShares blockchain.
With MXC and etc, the users' major activities are off-chain.
Actually, since we have bridges on awesome-bitshares, it's fair to add the centralized exchanges as well, as a new section. But it's not appropriate to mix them together, IMHO.