He walked for days, stopping at bars and restaurants whenever he felt thirsty, hungry or tired; mostly they were automatic and he was served by little floating trays, though a few were staffed by real people. They seemed less like servants and more like customers who’d taken a notion to help out for a while.

“Of course I don’t have to do this,” one middle-aged man said, carefully cleaning the table with a damp cloth. He put the cloth in a little pouch, sat down beside him. “But look, this table’s clean.”

He agreed that the table was clean.

— Use of Weapons by Iain M. Banks (Culture, #3)