For a second I thought this was about another RC company who ships slow and uses smart post...but HORIZON? Say it ain't so.
Chances are they used the cheapest shipping option, unlike their retail operation. Not sure if you got a better deal on Ebay, but HH has to pay multiple fees on Ebay, they don't really on their own site. Shipping lately has been odd, no explanation for some of the way the packages are routed.