Using your voice to control a device is useful. For starters in cars, controlling your smartphone by voice is just efficient and safe. Thereby safes it you from getting fined.
Most of us can’t do without our smartphones, they are our business, communication device and navigation. Thus being for the average person irreplaceable or so addictive that we constantly need them.
Most of us know that a lot retail stores have problems. The e-commerce website are totally breaking the stores unless they are part of the online strategy. If not they are at the mercy of the market, which in all fairness is controlled by Amazon.