What OF does is help with task prioritization and assuring you CYA by not forgetting important work. Are there value in these? Sure. $180 worth of value? Not so sure.
The average cost of an iOS app is far below $1.
Look, if it's too expensive for you, don't buy it. It's up for the Omni Group to decide on the price, and for you to buy it if it's worth it to you.
If enough people decide not to buy it that Omni notes sales are below what they want, then perhaps they'll adjust their price. But with thousands (tens of thousands? I forget exactly but the blog had the numbers) of people registered for the OmniFocus 2 beta, I sorta suspect there are enough people willing to pay the prices that they're not going to drop the price to $1 (LOL).