Paying as little as possible in labor is all this company knows.  Denying workers the means to document their shifts is a logical extension of this. 

(At least a couple of stores in Southwest are locking the write-in notebook up, away from the folks who need to use it.   Any wonder the company gets crappy marks for, "Conducting business in an ethical manner"?)

Federal law does require Krogrr to pay you for your hours worked.  Your state may have even more favourable (to you) requirements.

Management--who get their money regularly, automatically--probably have little-to-no idea what a demeaning hassle it is to have to come early, meander around, on personal time, unpaid, searching for someone with override capability or in vain for the locked-away notebook . . . just to document a shift, just to work for as little as seven dollars an hour.  Ridiculous is an understatement.

It's likely you're not obligated to show up before the time on the printed-out schedule.  For clocking-in purposes, the easiest thing to do is just show up when the schedule indicates.  Coming in early is a favor to management . . . and by denying the means to document our shifts, they don't seem to appreciate it.