Office365 is cloud based. The more you use it, the more you use Microsoft's resources, the higher the cost for them and maybe the higher the strain on resources available to others.
So for an Office365 bundle with x products, you pay the same price whether you use all x products or fewer. The fewer you use, the better for Microsoft and they don't take a hit on revenue.
Office 365 (actually Microsoft 365 these days) is, depending on what edition you buy, a set of cloud based services and licenses for installing the traditional desktop applications.
As with most Microsoft licensing & naming things it is surprisingly complex!
> As with most Microsoft licensing & naming things it is surprisingly complex
And weird. Like they don't want your money weird.
We have Office 365 for small businesses (or whatever it is called these days). A co-worker needed Visio for something. Nope. Visio is for businesses with Office 365 Enterprise subscription only.
Long story short, ended up with him having to buy a personal copy with the company credit card.
So for an Office365 bundle with x products, you pay the same price whether you use all x products or fewer. The fewer you use, the better for Microsoft and they don't take a hit on revenue.