My 2 pennies:
For the amount you paid, the bike should run on shitty gas or just about anything for that matter.
You also had the bike regularly serviced (I see in your other ride reports).
I think it would be understandable to have a regularly serviced bike make it accross the USA without issues.
All this talk of carrying spares and what not, piss on it. Why buy a $160 filter kit for a bike under warranty? You know the deal - you touch the bike and KTM says "you changed the last filter, we won't warranty it now"
Also, the dealer should have these filters in stock if they are so commonly needed.
At this point, KTM Corp can basically do nothing to get you back as a customer. Are you sure you can't do a trade in at the dealer? Can they get KTM Corp to ship the bike to Canada? At that point you can trade it in.