Pho Ha Noi, a Vietnamese restaurant in the South Bay, is charging 18% gratuity on every check.
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A recent diner posted a picture of their receipt, showing the surcharge applies to "parties of one or larger."
More than 5,000 infuriated Redditors responded, saying they've heard of surcharges for large parties but never this.
MORE: Consumers cry 'emotional blackmail' as self-checkouts solicit tips
Consumers cry 'emotional blackmail' as self-checkouts solicit tips