IDK, but this offered choice seems a little confusing to me.
Western Union, Money Gram, and Bank transfers are payment methods. you can be paid for some development or Selling Products through WU. You can't get any satoshis using only WU, you have to give something in return. Money, goods, service, or whatever.
I would suggest you check
https://bestchange.com and select "popular" on the left side. you will get statistics on which services are used the most in reality. at least based on the traffic of about 250 different exchangers.
Sir on coinbaazar users can buy/sell bitcoins instead of getting payments in WU,MG or any other, moreover all the trades are protected by escrow , so for both buyer and seller rights are protected , and other global payment methods, so there is no bounding for anyone if they simply wanted to trade/buy/sell bitcoins with bank transfers, MoneyGram or mobile pay..
Just think of it as the marketplace for accepting bitcoin as payments, and secondly exchanging/buying/selling/trading as well ...
Let me share with you an example- Suppose you are in USA providing services for web development and anyone who wants to avail your services , you can have a global reach on coinbaazar , you create an offer for buying bitcoins , and in your currency such as USD, as the person who wants your services have to open trade with you , wherein his bitcoins will be automatically transferred to escrow, so when you complete the job and everything goes smooth , the seller of bitcoins will release you bitcoins ... In this way .. both the buyer and seller can trade freely and globally....