Exactly my point - the $99 isn't a financial barrier, but, your average user isn't going to pay it each year, so it creates a minimum barrier between "Users" and "Developers" to provide Apple with some insight into how many developers they have.

Advance access to IOS kind of messed that up, (at lot of people paid the developer fee to access the next operating system) which is why application to the WWDC lottery is probably a better estimate of developer count.