And this is the problem Disney is going to run into if there ever IS a shooting at the parks - as a security measure, this new policy is completely inadequate.
Someone stockpiling weapons could hide them in a closet, under the bed, in the cabinets in the bathroom, heck, hide them under the covers of the bed...the CM would never find them because they don't look. They just come in, glance around, and leave.
If there's a shooting, Disney is going to be asked in court "Did you take reasonable measures to protect your guests?" Disney will say "Yes," and then the prosecution will bring up a dozen witnesses who will testify that A. the CM wasn't a member of any type of security and thus wasn't even qualified to do a thorough search or act if they saw something suspicious and B. the CM didn't even search the room, just 'glanced around and left'. There could be a bag full of guns sitting on the bed and the CM probably wouldn't even look at it twice.
So really, this whole thing is pointless. It's not a thorough enough search to be "security", and it doesn't accomplish any other purpose. It's just a lame attempt by Disney to cover their butts if something happens.