Water Heater Manufacturers - True Parts and Service Networks?

I'm posting below a nightmare experience I had with a Rheem water heater but I read a review on Consumersearch.com that mentions that Whirlpool also has parts and repair service availability issues. My horror story is just an example to illustrate a question I have: *Do water heater manufacturers have true service networks by which I mean both authorized service contractors and parts distribution? * *Are water heaters sold almost exclusively on price - is it so competitive that manufacturers are not willing to bear the expense of good service availability?* _Here's my story_: Water heater died two days before Thanksgiving. Knowing I had guests coming for Thanksgiving dinner, I bought a Rheem gas-fired water heater at Home Depot. Installed it (which took me quite a while as I am not a professional plumber). Pilot would not light. Called technical support. They told me they were over-nighting the required part to me to arrive the following day and that a local plumber would call me to schedule installation. Guy never called.