"...I guess this sounds a little cynical..."
Um.. yea

For sure it's a double-edged sword, and I certainly wouldn't call it a "gravy train", but our small business of less than 6 people has gotten free printers, scanners, hard drives, SCSI cards, tons of software over the last few years. We partner with Adobe, 3Com, Lexmark, Sony, Maxtor, FWB, Apple, Netopia/Farallon... etc. No Microsoft
"...EVERY manufacturer will tell you to go to hell if you complain to them, threats to take your business elsewhere carry no weight ..."
If you call up your rep and threaten to take your business elsewhere, you deserve to be told to go to hell. I'm sorry but this hasn't been our experience AT ALL. We have a very close working relationship with Adobe, Plextor, Apple and several other large software and hardware manufacturers, and we are not a large volume operation by ANY means.
If you purchase computer products in volume - then it's a pretty safe bet that you have some product insight that can help a manufacturer make their products better - it's in their best interest to keep you happy, and keep this channel of communication open.
Now there are exceptions to this - like anything in life. But our experience has taught us that if we communicate with manufacturers on a level where they feel that we are both on the same team, doors simply start opening for us.
I once had a rep drive over 100 miles with a RAID system - worth more than his car - packed into his trunk! - the company loaned the entire setup to us for a month just so we could make a presentation to a client. Not once did the rep ask how much volume our business was doing - or when theyr were going to get the equipment back. Now that is what I call service!
Workin': I'm sorry you haven't had the same experience in the reseller channel - maybe it's time to look at who you're partnering with, or how your company represents itself?

Just a thought - no offense intended.