Under product management > tools > product groups, we can make product groups. But I can't think any uses apart from you can sort or group products in BE.
In isotope, we are grouping or assigning products to pages from site structure and in filter module we can then list product from current/all/prarent category.

This "product groups" where can I use? If its just for a visual grouping in BE, do you make a product groups mapping/similar to site structure?