To put US$2,350 in perspective: As long as 3 years ago people were predicting it would become more difficult to renounce under these current conditions.

This could be why the consulates slowed down their renunciation bookings — to take advantage of the up-coming price increase.
1. slowing down appointments
2. 2times fee raising
3. making it more difficult all around to relinquish or renounce
Please keep in mind  that the fee should be collected before
conducting the ceremony and administering the oath. If a renunciation is undertaken but not approved by the Department, the fee is not refundable !!
State Department’s justification is pure nonsense. They are simply taking advantage of the increase in demand to renounce US citizenship. As the predicted price of future tax compliance goes up, the demand for CLNs will go up as people do the math, turn down the thermostat, tighten their belts, and figure out they can afford the CLN but cannot afford future compliance.  State will respond to increasing CLN demand by making procedures more onerous, which will raise their own costs for CLN issuance; they will certainly pass those costs along to renunciants. CLNs are a new growth commodity and just beginning to enter a super cycle and I would not be surprised to see counterfeit CLNs start to pop up.

Why is there still no fee for relinquishment, considering that they are much more costly to process than renunciations?

That’s probably next. Relinquishment itself may even remain technically free, but the paperwork processing fee if you want a CLN will be $2,350.
http://www.nostate.com/4089/at-long-last/

A new study by the National Bureau of Economic Research shows 50% of Americans would struggle to come up with $2,000 in a pinch, for example in the event of an unanticipated car or home repair, a large medical bill or legal expenses. Roughly 28% said they “certainly” would not be able to cope with an unexpected $2,000 bill if they had to come up with the money in 30 days, and another 22% said they “probably” would not be to able to cope.

So what are you supposed to do if you are like those 50% of people and cannot afford to renounce, cannot afford the expense to relocate yourself and your non-U.S.-citizen spouse to the U.S., and cannot afford the expense for an accountant to file 3520s for you on a mandatory retirement account you cannot close?
http://money.cnn.com/2011/05/24/news/economy/americans_lack_emergency_funds/index.htm
http://m.state.gov/md231128.htm