Most travelers believe that in-room electronic safes are effective for protecting loose cash and valuables when they travel. Indeed, most of the time this is the case. However, a safe alone is not an effective deterrent against a crook who may have a master code or electronic equipment to override the device.
Although the video says that the Milockie prevents theft, it is really just a strong deterrent. A clever hotel crook would use a master code to help themselves to some, but not all of your cash. They may also use or make a copy of your credit card, and then put it back in the safe. However, they are likely to just go elsewhere when they are surprised by additional hardware on the safe.
Traveling in Latin America comes with its own special set of risks. Poverty and economic scarcity is common. Gentleman tourists often carry large sums of money, either for casino gambling or entertainment. They make tempting targets, especially for those in the hotel industry who know their habits.