Packing things into a GPU texture is probably the #1 most common use. If you played a game today then your computer probably spent some time packing rectangles into rectangles.
https://mozillagfx.wordpress.com/2021/02/04/improving-textur...
Plus there are a fair few programs that render text by rendering the font into a texture atlas once and then using the GPU to copy from the atlas. Your terminal emulator may be doing this, for example.