A number of small Shopping.com merchants emailed me in the past month to look into PPC bidding on Shopping.com (SDC) as they couldn’t figure out 1) why they were being charged above their minimum bid + the 30% season rate increase and 2) why they were charged clicks at multiple rates.
I looked at my own account and was also confused. On one day (December 19th), for Electronics > MP3 and Digital Media Players, I had click charges for $0.91, $1.04, and $1.07:

The minimum bid for Electronics > MP3 and Digital Media Players is $0.70 and with the 30% seasonal increase would total $0.91. Include my add-ons: Shopping.com charges $0.10 for a logo listing and $0.02 for a phone # listing, and the numbers still didn’t add up:
Minimum Bid: $0.70
30% Seasonal Increase: $0.91
Logo listing: $0.10
Phone # listing: $0.02
Total Cost: $1.03
So how did SDC come up with $1.04 or $1.07?
Turns out the 30% seasonal increase also effects the logo listing and the phone # listing, so I’m getting charged $0.13 for the logo and $0.026 for the phone # listing. This wasn’t explicitly stated by SDC in it’s announcement of the seasonal pricing increase as seen in the Merchant Account Center (MAC):

As for the multiple rates, while SDC will always display the add-ons (logo listing, phone #, etc.), not all partners/co-brands do – and if the add-ons are not on a partner/co-brand site, the merchant obviously doesn’t incur the cost.
Hopefully this clears things up, but if there are any additional questions, please comment below. I spoke with SDC about these issues…the company is working to improve reporting functionality, and I’m sure future rate increase notices will be a lot clearer.