I can't imagine what "these programmes" you're referring to could be that could possibly be cheaper than providing full-time personal assistants to every visually impaired person in your area. The statement sounds pretty unlikely, and really demands a very reliable source, but you've provided none for support.

Beyond that though, even if this were true, the added expense alone is not enough to justify treating people with disabilities as second-class citizens, who have to be "minded" rather than allowed to freely navigate their own communities, "because it's a bit cheaper that way!"