Let people decline an expense without requiring a public account of their finances.

Asking why someone cannot afford something turns a simple no into a disclosure. Money is tangled up in things people may not want to explain in front of others: a debt, a wage, someone else’s illness, a decision they regret. Faced with that, most would rather pay than lay it out. A refusal accepted without inquiry costs you nothing at all.

When somebody declines a cost, say that is fine and move on to the next thing. Offer the cheaper option to the whole group rather than to that person. Never ask for the reason where others can hear.