I doubt many bonafide restaurants will go for this, restaurants tend to fully prioritize making money from happy customers, and it's mostly older people who spend the most money collectively out at restaurants, for several reasons, and most older people already don't like having to use their phones, it won't necessarily be most restaurants refusing the qr code trend for ideological reasons but definitely for protecting profits, fast food chains and low end places are more popular among the the younger generations who are mostly low income wage workers who rarely have the time or money for nicer sit down restaurants, and the younger generations are far more comfortable with frequent phone use (generalizing, special exceptions aside), so I'd expect to see qr codes become more and more common for fast food and takout