Ignoring status for a moment Club Europe offer the following benefits in my view:
Lounge access at many airports
A little extra space on board due to the middle seat
Some complimentary food and drink
2x32kg checked baggage
Obviously status negates some of these but the extra bags can be very valuable for some people. For someone without status on the right route and needing the luggage allowance CE could easily be worth a couple hundred more than economy.