If by, "regular database" you mean the traditional banking system, I've already laid it out for you. You can't send money from a bank to someone without a bank account. The cost to use a legacy payment system like Moneygram is prohibitive - you can't send $10. The regulatory hurdles to send and receive money from a legacy payment system, even if the cost wasn't prohibitive, often prevent you from doing so, even when everything is totally legal and legitimate.
>Why are you selecting litecoin as your example, out of curiosity? What's the difference?
The transaction costs are very low, and the blockchain transactions take place relatively quickly. Sending $10 to anyone in the world might cost you 10 or 15 cents and take 10-30 minutes. I am far from a crypto wizard, but was an early adopter for exactly the reasons detailed above.