Adding fiat to transactions and deposits is a strategic step that can trigger the growth of members and investors. For novice investors, this step is something that makes it easy for them to invest in cryptocurrency and I think there will be many exchangers who follow this Binance step
It's indeed a very great strategy for Binance. You can imagine what if most of the fiat currencies are on their exchange, then it can every single country that the other exchanges doesn't have.
They'll get most of the traffic and traders worldwide.