They don't pay attention to cell phones unless you are taking pictures. I've made and received calls while playing blackjack. Everyone has a phone.
Thank you for being the voice of reason in this thread. I suspect many of the
hens clucking about casino security Ninja's jumping-down from the ceilings and popping-up out of ashtrays if they see you with a walkie-talkie had security initially paying attention to them for reasons other than radio-related, if you get my drift...
As-with most things in American society, if you're engaging in activity that despite being lawful, you have reason to believe is somewhat unusual/suspicious for the environment, simply be discrete about it and as a general rule, try not to look or act like an idiot. Following those sage words of wisdom (common-sense to most, but evidently not all of us), I've wandered around dozens of Vegas area casino properties, large & small, with a scanner in my pocket collecting ELINT via Close-Call, a Motorola DTR-650 or 700 on a beltclip or in my hand being used, and a medium-frame pistol concealed on my hip. Plus of course a cellphone. Sometimes I even carry a Motorola XPR7550e on my belt, which is usually the same LMR that the casino issues. I don't set it on a bar counter (for some reason, it scares the nice young women from flirting with me), but I've set down all sorts of radio gear on the table at my marathon casino buffet sessions. In probably hundreds of hours over the years on/in casino property, I've been stopped ONCE, and that was for blatantly taking photos with my iPhone while exploring a new casino that'd just opened (Lucky Dragon...). The Security Manager walked-up to me (with a uniformed officer loitering nearby), and asked if he could speak with me. Instead of confessing all my sins, bending-over & spreading my cheeks while begging for mercy, I said that yeah, I was taking photos of the brand-new place as I explored it & was trying to make up my mind which of their restaurants I'd get an early dinner at. I was asked to delete the photos that showed the "cage" (the cashier area). I obliged. Never asked for ID, never escorted to their security office, never asked about the antenna sticking-up out of my pants cargo pocket, never asked to leave the property... I was a little embarrassed nonetheless, but I wandered around for another 10 minutes or-so, taking more photos, and then I left, doing some counter-surveillance tactics to try to minimize the chance of them using CCTV to see me go to my car in their parking structure & getting my license plate. MAYBE they screen-grabbed an image of me & passed it to other casinos, PROBABLY they had no reasonable, articulable suspicion to do-so, especially with most other properties being busy with drunk & obnoxious people, "campers" (the PC-term for homeless), etc. but I continued then and continue now to visit lots of Vegas casinos without issue, discretely carrying a scary gun and carrying/holding/using what some of you suggest is even scarier to the casino security industry -- a radio.
Some of you have been focusing too much on those Die-Hard movies & the terrorists using walkie-talkies.