Fair point Joseph. Walk Your City is a prototype - low cost and easy to test. The design teams have budget constraints and the projects are temporary (3 day festival in April). Based on the feedback from the prototypes, the city can then determine whether more permanent and more expensive wayfinding is a priority for the redesign of Market St.
I like the idea of repurposing un-used newspaper/magazine kiosks for touchscreen wayfinding. Although you could argue that most people already have a touchscreen in their pocket, which transfers the hardware costs to residents. Perhaps there is permanent wayfinding signage with clear instructions for people to access it with their own devices.