People misusing the single rider line is one of my biggest pet peeves. The single rider line is only for people who intend to ride alone. It's a great idea for filling up the empty seats caused by odd parties, but some people abuse and/or can't understand it and it drives me nuts.
Here's a good article by Robert Niles that puts my anger into words: http://www.themeparkinsider.com/flume/201601/4926/
Here's a good article by Robert Niles that puts my anger into words: http://www.themeparkinsider.com/flume/201601/4926/