That was my exact line of thought that led me to ask this question but I don't want to automatically assume anything. So maybe, if you go back, you can confirm if this is the case.
I try to be reasonably creative with using the tools that we have in Madden to accomplish certain non-gameplay things. I wonder if this would inadvertently make pre-game subs and mass substitutions possible or they planned it that way. Probably the former but either way, I am glad if it is possible.