[sanderjd]

People frequently and vastly underestimate how much people are willing to pay for the convenience of paying somebody else to do something for them.

[ryanklee]

Yes, but only to the extent that they themselves aren't willingly paying for the convenience of having somebody else do something for them.

When they are, well, that's just common sense. When they aren't, well, those who do otherwise are just being indulgent.

Housekeeper? Indulgent. Startbucks coffee? Convenient.

The (social) legitimacy of expenditures is usually a matter of custom, not economic analysis.