According to The Sun, the boyband were denied entry to several establishments during a break in their US tour as they are all under 21, the legal age for gambling and drinking in the state of Nevada.
A source said: "The boys were hoping to go wild in Vegas by boozing and gambling into the early hours. But security at every casino in town knew who the lads were and threw them out."
They added: "Finding out the hotel suite they had ordered wasn't the one in The Hangover was also pretty annoying."
The 'What Makes You Beautiful' stars were said to have stayed at the city's Palms Casino Resort, in a two-floor suite with its own hot-tub, pool table and basketball half-court.
Band member Zayn Malik was this week accused of "pimping Islam" to US fans by right-wing blogger Debbie Schlussel, who also called Malik's keffiyeh scarf the "official garb of Islamic terrorism".
Watch One Direction perform 'What Makes You Beautiful' on iCarly below: