I too have witnessed questionable treatment of bikes, and I always figured it comes down to the individuals doing these boring, physically tough jobs. A few are going to be the types who for whatever reasons in their lives just dont give a flying you know what about other peoples things.
Its a big roulette wheel when travelling with bike and I figure its just bad luck to land or not land on one of the few angry sons of guns.

Most of what the baggage handlers can dish out can be protected against by proper packing. Mine has survived damage at the hands of the baggage handlers after many flights. I did have some minor damage once as a result of a TSA klutz. I have actually seem my bike boxes much worse for the wear when shipped by UPS or FedEx, but didn't suffer bike damage with them either.

I just went to a UPS/ Fedx store and was quoted 140$ to ship a bike one way from Tucson to Salt Lake City. I got on ship bike and the price is <40$. Almost seems too good to be true. I will give it a shot and report on how it goes.

Have you checked out bikeflights.com? I would get an on-line quote from them first. It's easy to do. I shipped from Philly to Missoula, MT back in June. Wildly overestimated the large bike, bike box, racks, stove and fuel bottle at 90 lbs. 4-day shipping rate was $68, plus $5 for pickup from local bike shop.

I looked at various shipping options to get a bike from Canada to Portland earlier this year, and as soon as you shipped across the boarder, the cost rose to the stratosphere -- I ended up taking the bike on the Air Canada plane with me, and it arrived safely. $50 for the bike, and $25 for the checked luggage.

So if you're starting in Seattle, a shipping company might work, but probably not if you want to ship to Vancouver or Victoria.