When the group and their pals visited the Abu Dhabi Grand Mosque on Dec. 29, they raised some eyebrows by posting goofy Instagram pictures.
Gomez, 22, got the brunt of the hate when she posted a now-deleted picture of herself popping her leg out to show off her bare ankle -- a sign of impropriety in the Muslim culture.
"I was just thinking, why purposely go to a sacred place and do something considered disrespectful?" one commenter wrote.
Gomez didn't comment on the controversy, choosing instead to delete one of the images while leaving the group shot up.