The answer is yes, the radios are yours, not someone else's. However, the repeater owner doesn't want you to use them. Not all FRS radios have Roger beeps; some do not. Therefore, I advise you not to use Roger beeps on the repeater. You can communicate with your family using Roger beeps, but please refrain from using them on the repeater.
to those who are new to this MDC is NOT BEEP is an ID.