Not sure how many gateway operators/owners actually take the time to review the messages traversing their gateways, but I highly recommend doing so weekly.
I typically review my gateway's traffic every Sunday evening, looking for any suspicious activity. This could be foul language, illegal activity, et cetera -- anything that might violate Part 97 rules. In my reviews I have found several messages that should not have been sent and either contacted the sender directly, reported it to the Winlink team, and in a couple rare cases even forwarded the info to authorities.