This Is the issue the widely travelled person has. While tipping 15-25% is essential in the U.S. (In some places, but not others), in Europe it's clearly optional (unless there's a service charge), in the Far East it's often an insult.

That's not a problem, but more unworldly travellers will export their own tipping culture. Austrailians not leaving a penny in a NY diner, or Americans leaving 20% to their Beijing taxi driver.

Tipping is a minefield for anyone with an outlook beyond their own local area, and it would be far easier if the world was the same (Currrency, language, tipping). It's not though - and variety is the spice of life, but when it comes to Uber it is - no tips, job done.

Tips / bribes drive down wages - the business owner can pay less by assuming the customer will make up for the wage.

Uber does not do tips, same as when I buy some soap from CVS. If that changes, uber will be able to pay less in tippy countries and it leads to the mess we have elsewhere where people rely on tips.

There's an argument as a British citizen in not legally allowed to tip, especially in the U.S. Where it's accepted to be a required payment.