Not necessarily majority - it's an interesting ability of capitalism over many other systems - multiple solutions to a problem can co-exist. As long as enough people still demand it to make it economically viable.
With "just walk out" the friction is extremely low. It might see less pushback than other technological approaches. However I have to think security will be a major issue. If I can rob the store by just leaving my phone in my car or leaving a cheap phone in the store while I walk away with the products. Tap-in/out gates are probably the best bet, but can still be tailgated, so you'll need to have pretty tight security and monitoring ready to beat anyone down who doesn't pass the checks or looks fishy at the gate or in store attempting to fool the system into believing they're another person. Or write those off as losses, I suppose most retailers today already do a lot of that.
Suppose the minimal cost solution has a cost of c.
Suppose there is an extra "human touch" factor that costs x extra. So the total cost is c+x.
Suppose there are n customers, of which m prefer the human touch.
In a world with humans everywhere, it costs everyone c+x/n to deliver a product that satisfies everyone.
In a world where two solutions are competing, one with humans and one without, it costs c+x/m to deliver a product that satisfies m, and c to satisfy everyone else.
The subset m that prefers the human touch has to pay more. But notice there's no magical majority cutoff here; that's not how it maps out. It's a curve that gradually increases the cost the lower the m:n ratio is, until it becomes a very expensive boutique service that only very wealthy people can afford. And the increasing slope makes it hard to fight.
It is in fact people with the least sensitivity to price and preference for the human touch that will help maintain the status quo. And those people are usually in the minority.
