Exit and entry stamps at Bahrain border

Hi guys

I exited and entered KSA over the weekend without problems however they did not stamp the passport pages either time. I've heard since it's all computerized they sometimes don't bother or forget stamping. I even went back to ask for a stamp, the guy just shoo shooo me away, go, go  go. Like I didn't need it. No, no, no he said. Anyways, I don't want to be responsible for someone else's mistake or negligence. Can anyone else confirm this experience? I am on a work visit visa. Every 30 days i do a visa run to Bahrain. The validity of my visa is 90 days from the issue date. I have an original entry stamp from the airport, so no problems there. It's just the entry and exit stamps at the Bahrain border ever 30 days I'm worried about.