In Minecraft, buildings can take a lot of effort to build, but are very easy to destroy. Chen Mo had also made changes to amend that.
Guilds can pick one or multiple plots of land to claim it as their own, they will have absolute complete control over all the plots in the areas. The guildmaster can accept and kick guild members freely, and only players with permissions are allowed to place or destroy blocks in the areas claimed by the guild.
The 'areas claimed by the guild' was more or less a territory, allowing them to feel the greater sense of belonging, as if the plot of land was their home. Nobody would destroy their home for no reason.
As the guilds grew (dependent on number of players, time, and area built), the area claimed by the guild will also become bigger and bigger. Two guilds cannot have claim over the same area, and if that happens they'll have to combine guilds to declare war.