I have seen some tables where it alternate rows has subtle different color, and it is been said that it increases the readability. I wonder why is it better to do such practive.
The alternating colors help with readability when you have to read long horizontal datasets - you don't lose your place as often thanks to the color (or border!). But keep in mind that if there's not a whole lot of data, the different colors can make it seem like certain data is being highlighted when it's really just a different color. So one way isn't better than the other, it just really depends how much data there is available.
Here's an awesome article about data tables you can read: https://uxdesign.cc/design-better-data-tables-4ecc99d23356.