I always start the phone call by asking for a supervisor and explaining that what I need is different from their routine customers and there is no need for me to waste their time, especially if I am going to be 'yelling at someone' before I get finished. Person always happy to get a supervisor on the line, and a couple of times I have had to ask for their supervisor.
Lately I've been having good success at using Twitter when I run into a roadblock with a company - something about blasting out a generalized complaint all across the world (as in "Why does XYZ Company treat customers so badly" etc) will get a lot of retweets and a DM from the company giving me a specific phone number of call and someone who will talk to me.