USPS and UPS would just say they weren't responsible because they didn't use enough tape causing the strap to break. WTH wouldn't they have a set of safety chains/cables if they were using straps?
You will rarely see chains used in heavy lifting. Worked as a rigger for a couple years. Used gin chains and such on lighter stuff. When we started getting into real weight it was cable chokers or nylon straps. Nylon works well if kept in good condition and not over loaded. I worked a couple derailments before becoming a locomotive engineer.