I think $10 is too low an estimate.

An AirFanta 3Pro on low (2) is 5W, which is $10 on average (but more like $15 in high $/kWh places like MA and CA).

Some people are paying north of 0.50€/kWh (after tax), so this amounts to 22€ annually.

The point stands. If you care about this, it's a personal choice whether that comfort is worth ~20€. I would wager many people say it is.