I'm right there with dsmom. We've been comped and last year I added it for $50 a night because it was worth it to us.
... and that's considering the fact that we never made it for the appetizers because the timing never worked out, and there are so many good restaurants on property, that we never had everyone say, "Let's eat the free buffet at Portofino tonight" (regrettably).
The convenience was the biggest factor. I used to hit the Gelateria every morning before the parks for coffee and every night before heading up to the room for coffee, ice cream, etc. (side note: Does anybody actually keep their Gelateria cup all day for the free refills?)
With Club access, we all get breakfast covered every day. I'm fine with coffee and a bagel w/ cream cheese. Wife and kids were fine with the yogurt, croissants, trail mix, cereal, toast, juices, milk, etc. They also had to-go cups and lids for coffee and bottled water you can take to the parks in the morning.
Mid-day we'd sometimes catch some of the little snacks, but primarily we'd take advantage of the sodas, water, and coffee.
Next to breakfast, the other biggest advantage for us was the night time milk and cookies. We'd load up and take it back to the room each night.
The other thing we used was the internet access. Need to get previous semester's grades while we're there, and having the computer in the lounge saves us from having to bring down the laptop and pay $10 a day. Although last time we tried that, we never could get the software to connect us into the hotel's LAN anyway.
Bottom line - like everything else - it depends on what value you place on the different items. How many people you have - how far from the lounge is your room, etc., etc. My guess would be that for most situations, $125 a day for access is probably too steep to justify. You should be able to do much better - unless that $125 premium includes the cost to upgrade to a deluxe room also (in that case, I'd say it is worth it)