I’ve read recommendations of 30% these days
Bloody hell! Anyone saying that is trying to take advantage of people.
In the example you give, the business owner increases prices in line with inflation but hey! the workers need a pay increase too, and I'm not paying them more, so the customer should tip more.. so the recommended tip amount increases from 10-15% to 20-30%. But this is not in line with inflation, this is an exponential increase.
A lot of people won't recognize this as people don't generally understand exponentials that easily.