Per the Laughingplace website:
Shopping Service
The LaughingPlace Store now offers a shopping service for items sold at the
Disneyland and Walt Disney World Resorts You select the item you'd like to purchase from our Shopping Service pages. We purchase the item and send it to you. We charge you the cost of the item plus a shopping fee and shipping.
Note: LaughingPlace.com is an independent company offering this service. We are not associated in any way with the Walt Disney Company.
Shopping Fees
The shopping fee is automatically included in the price of each item when you browse the store or view the shopping cart.
The fee charged is based on the cost of the item at the theme park (including sales tax) and which theme park it will be purchased at. The fee is included in the price shown.
The Price at The Theme Park
When we purchase items, we do not use an Annual Passport or Cast Member discount. We pay full price for the item and the price we pay is the price you pay (excluding shopping fee).
So, their prices are more expensive because they charge a small fee to go to the parks and buy the items for you. Buying from them does cost more than if you purchased something at the parks yourself, but I have found that they are much cheaper than some of the other WDW merchandise shopping services, if you just HAVE to have something between trips or before you arrive. In fact, I ordered the Wishes CD from them, and it was only a dollar or two more than if I had called WDW Merchandising and ordered it from them (their shipping prices are the killer!).