Why is it beneficial to use the same routes? Why wouldn't you just change the route?

The question of "why make something modular?" is a common one. It might seem like the modular approach is more work up front, and sometimes it is, but it's usually worth it in the long run. Modular design makes it easier for you and others to read and understand your code in the future, and it'll make changing things in the future quite a bit easier.

As a simple example, let's say you build a site for a client, and they want the following routes for their online store:

/products/
/products/mens
/products/womens
/products/kids

Months go by, and now the client wants to split the "products" route into three different routes, like this:

/apparel/
/apparel/mens
/apparel/womens
/apparel/kids
/shoes/
/shoes/mens
/shoes/womens
/shoes/kids
/swimwear/
/swimwear/mens
/swimwear/womens
/swimwear/kids

If you have the mens, womens, kids routes separated out into their own namespace from the beginning, it's trivial to meet the client's request and apply those routes to apparel, shoes, and swimwear instead of products.

Alternatively, let's say they want to change it from products to items. If you have a products router set up with /mens/, /womens/, and /kids/ routes, then all you have to do is change the name of the products router, as opposed to having to change every route individually.