It doesn't matter if the whole store will be dinged by the regional director, or even by the CEO him/herself: this is illegal. The labor law (e.g. the Fair Labor Standards Act, or FLSA) requires that accurate time cards be kept; that employees be paid for all hours worked; and that employees be paid overtime if/when they work more than 40 hours in a single workweek. Your wife has a potential claim for all unpaid hours and overtime she should have received, but did not. A good way to proceed is for her to contact your state's department of labor to file a wage and hour complaint; the DOL may be able to help her without her having to hire an attorney or go through the trouble and time of suing.