not that hard if you think about it. Two per case, 5 cases, will easily fit on a bellman's cart. One or two trips to a truck or van in the parking lot from a room for 5 cases and additional supplies. Even if it took more runs than that, easily accomplished in less than an hour. Would not have looked suspicious at all, except maybe to someone versed in firearms. Then you might wonder why so many, but Nevada is where many, particularly Californians, take refuge to shoot and train with their firearms, so again its not out of the question that some normal Joe has come to Nevada to shoot legally, and is just enjoying a night in Vegas afterwards.
I wouldn’t want to leave my guns in a hotel room, while I ‘enjoyed a night in Vegas’.