Well, the idea is that students would buy the materials needed for the classes at the RS they're in. A bit like Wine stores and Home Depot do. But those are huge facilities and spending a little money on a classroom isn't a big deal percentagewise.
So your general points stand.
Isn't that exactly the quandry RadioShack is in, though? They need to pivot, fast and hard. Rip out those stupid mobile islands and the hard-sell mobile device employees and host maker-spaces.
Classes are a whole other thing. You need to market them hard, you need repeat business, and if you're not running them every day you're spending a lot on retail space for a limited return.
Also, Internet tutorials. And limited interest in most of the world.
Unless you can supplement classes with a stream of high margin sales, they're not going to keep you afloat for long.