Best practice for loading source data into a base application?

I understand from Backbone docs that it’s best to load model data into an application by inserting it into script tags that display on the page’s initial load.

I understand that this is done so as not to send additional requests to the server, which will speed up page loading.

But...

Is that really a big difference? I am currently sampling half a dozen models and collections on the loading page, and everything seems to load very quickly.

Are there any other reasons for using this proposed data loading method? If not, for me this seems like an extra effort for minor gains.