Chad Morris wanted to make a point about preparedness. You never know what can happen over the course of a football game, so it's important to stay ready for all possibilities at all times.
For instance, a team could lose all its deep snappers over the course of a game, so walk-on linebacker Grant Morgan may be called in to snap. A team's holder may be unavailable, so walk-on defensive back De'Vone McClure may have to come in in relief. And even if that happens, walk-on kicker Conner Limpert will still be expected to make the kick.
Which he did, putting all three players on scholarship.