1. Surely the long term plan is to not keep these relics in a gargantuan warehouse but instead to put them in a museum(s) — with free entry no less — so that the tax paying public can enjoy them.
2. Further, collections of relics that relate to the site of each station on the line could be displayed in each.
The tax paying public aren't going to pay for that.
The existing collections can just about barely justify free entry. Most museums have a vast secondary collection that's not on display already. These items are going in a warehouse because there isn't enough money to do archaeology on them any time soon, let alone prep them for display.