Beware of Johnparts and SuperT

Excuse me if this sounds like a silly observation, but isn't $150 for heat-shrink and tubing rather excessive? I do my own wiring and these items are quite cheap. For just $60 i bought enough tubing and heatshrink to last me a few years! And the Ozito heat gun i use (ok, its made in China but it had a 3 year warranty and it is still going strong 4 years later) only cost $30. The amount of tubing and heatshrink required to do one engine loom would be an insignificant cost IMO, perhaps $20-25? And should have been taken into account in the first transfer of funds.