Why does this currency have a large trading volume?

Yes, EOS is a good project. Which is similar to Ethereum but has some technological difference. Such as EOS can perform many transactions within one second but Ethereum can't. Also, EOS doesn't require any transaction fee. It is totally a free platform for the transaction within the platform. So, EOS has advance and smart technology for which they have become popular.

[ Note: Their main net still not launched]

When it will launch the price may increase enough.

Thanks for your question. Hopes you got the answer.