There are, at least, two groups by this name. Ballyhoo (without the exclamation mark!) is a South African group who had a huge hit in 1980 in their homeland with their single 'Man On The Moon'. This South African group is still going strong. The other group with the same name (but with the exclamation mark!) is from Maryland, USA, a modern rock/reggae party band, active since 2006.
These are photos from concerts where Ballyhoo! played, so they may be of other bands that played the concert as well.
Vans Warped Tour 2016 Aug 7, 2016 Pomona, California, United States Uploaded by Hallowx13
Vans Warped Tour 2016 Aug 6, 2016 Mountain View, California, United States Uploaded by Rivrose
Vans Warped Tour 2016 Aug 2, 2016 Glendale, Arizona, United States Uploaded by Haley Penny
Vans Warped Tour 2016 Aug 1, 2016 Albuquerque, New Mexico, United States Uploaded by Mjhudson81
Vans Warped Tour 2016 Jul 31, 2016 Denver, Colorado, United States Uploaded by Sienna Araya King
Vans Warped Tour 2016 Jul 27, 2016 Maryland Heights, Missouri, United States Uploaded by Morgan Berk