I posted over in the mechanics forum, but at this point I've got thousands of miles on electrical tape and what's more, I'm not the only one.
Sure, rim tape is cheap and if it were just a matter of the money I wouldn't think twice about it. It's really the realizing at 9pm on a weeknight or 11am on a Saturday, as you're working on your bike in your pyjamas, that you forgot the damn rim tape. That's when you turn to other solutions.