I think the question is entirely valid and not stupid at all. I think Dazbo has happened on to something that can be explained musically. The harmony is largely stacked 2nd inversion, ie instead of CEG (root position), EGC (1st inversion), it is largely GCE (2nd inversion? making for that distinct "barbershop"sound. Also the contrapuntal part singing where not only are there different notes but entirely different rhythms that are sort of compatible, is either something you like or don't. It is also smarmy and theatric and has a fair emphasis on High Tenor and low bass "show off" lines.

That said, I rather enjoy it for what it is, very very talanted performance if it is done well. I wouldn't want a steady diet of it, mind you, but we went to the southeast regional barbershop competition on a lark last year, and it was a very enjoyable evening.