I'm not sure if that's the right question. Areas can be overkill for small projects, but it's hard to imagine a non-trivially large project not using areas to help keep classes organized.
I use MVC Areas for the enterprise and love several things about it:
- Typically people are working on a feature within a given domain (e.g., Search, Checkout, etc). If the area names correspond with your business domains, MVC Areas help reduce the time it takes to implement a feature, because the related classes are easy to find.
- MVC routing gives you a ton of flexibility over how how structure the URLs. I used to use the Action Controller "pattern" but for non-public facing URLs I've just fully embraced the Area default route to make things easy.
- Areas give you the distinct advantage of styling and, more importantly, encapsulating behavior at a site-section level. Each area gets its own web config where you can control the base view page or add managed handlers.
You're absolutely right that services should be in separate projects / solutions altogether, that abstract the data access via repositories, in an environment where multiple clients can access common business functionality.
But MVC Areas are great at providing some order to the UI / routing chaos as a web project grows, which, to me, is invaluable, regardless of context.
