He says bellmen and valets rely on tips for much of their income, but some hotels were slow to bring them back and now have fewer bellmen and valet attendants working, so they sometimes have less time to talk with guests and receive tips.

Source: https://www.hawaiibusiness.com/tipping-culture-post-pandemic/

However, when they tried to assault Eugeo and Kirito's valets, they crossed a permanent line.

Source: https://www.cbr.com/sword-art-online-strongest-villains/