What's up with that?

I'm after another curved turnout as I'm moving the depot area (again...). So off to the interweb I went, finding that my local hobby supplier - Hobby City - has them at $52.90. Ouch.

Further searching on Google revealed that Mack's Track in Wellington had the turnouts for $39.21 (excluding postage), and Main Station had the turnouts for $35.58 plus $4.00 for postage. So I naturally ordered from Main Station...

And this is the part that grinds my gears. When you go to process your order, you've got to select a "dealer" - the Auckland region has Hobby City listed. So, Hobby City supplies the turnouts to a website for $13.32 cheaper, posted, than they do in store? That doesn't make any sense at all.