It looks like the webbing straps are used to bind the aluminum base plates to the truss segment that the base plate rests against. (As opposed to the plates being bolted or otherwise clamped to the truss member.). Gosh, I hope I'm wrong. Yikes! Mark C.
Finally the 2 guys in the picture... the guy on the left strikes me as the "band guy" who's explaining to the roof owner on the right, that he's not letting the band on stage and the owner is about to have an aneurism.
A few observations;
Are those your suspicions Shane?
It's the kind of spigot truss that uses couplers and pins. I don't think I've seen this in any domestic roofs from Thomas or applied.
Can anyone tell me what these straps are being used for?
That says everything I need to know....Apparently the roof in question belongs to Illusion Sound & Light, out of Ephrata, PA. This photo isn't on their website though, go figure.
http://www.illusionsoundandlight.com/index.htm