1) OpenBazaar is a decentralized marketplace, not an exchange.
currency can be exchanged in marketplaces just fine.
Here are other decentralized exchanges if you prefer a very restricted marketplace that just focuses on tokens:
https://bitsquare.io/http://coloredcoins.org/http://www.coinsigner.com/2) Alright fine, bitcoin wallets allow automatic creation of new addresses to recieve bitcoins..But again it still isn't in favor of the average joe. If for ex: Amy gives John her (x)coin address to send money to, and John sends. Then Amy gives John another bitcoin address for John to send money to, and John sends, then an observer would be able to guess that those two wallets that John sent bitcoins to are linked or owned by the same people(s). Also, I'd assume it would be a hassle and get tiring having to continually give people new addresses for them to send bitcoin to.....It's all very inconvenient, and that's where altcoins with built in anonymity come to play. Also darkwallet is a 3rd party approach to anonymity, anyone with sense would know to avoid 3rd parties when it comes to using bitcoin(that includes web wallets).
Are you familiar with stealth addresses, coinjoin and coinshuffle?
https://www.darkwallet.is/With stealth addresses you never need to change your address.
1) I responded to this quote from you in which you say that some Bitcoin Wallets create addresses automatically and which I said(read above posts), that that's still inconvenient:
Hassle of creating new addresses? BitcoinQT, Mycelium and many other wallets do this automatically now with no effort from the user.
Additionally:
http://darkwallet.is/2) Coinjoin is known as not being the best of ways to anonymize yourself. For Ex: You can recieve your own coins back when using coinjoin if there aren't a sufficient amount of coins participating in the mixing... Is stealth addresses implemented in the Bitcoin core(QT Wallets), if not then there's no point in bringing it up, as I said before that 3rd party addons should not be used by those dealing with Bitcoin/cryptocurrencies...