The title of this paper implies a number of common assumptions, which the paper subsequently questions. Asking what inclusion costs implies the current situation is exclusionary, and suggests there is a possible, different, inclusionary situation albeit at a measurable additional cost. This paper takes the perspective of those excluded in the current situation and questions the assumption that the current exclusionary situation necessarily costs less than an inclusionary one. To do so, it presents a novel economic methodology that measures and compares cost and effectiveness of both the current situation and a situation seen as optimal by those using Assistive Technology Systems.