'Royal baby shower' pieces shortly before George's birth, 'Corgi line', 'Royal Wedding' pieces just before the wedding in 2011. All Party Pieces lines. Yes, you could say that all companies that sell stuff similar to Party Pieces were promoting similar things before Royal occasions, and why should the Middletons miss out? To me however, and to others, that is a very very thin line between commercial enterprise and profiting by a Royal connection.
But its a free enterprise. No one is forced to buy anything from the Middletons. If the people of Britain think they're cashing in they wont buy the merchandise and they go out of business.
Prince Charles sells royal baby related merchandise through the Duchy of Cornwall. The royal collection made a bundle from Kate's wedding gown
The Middletons are in a competitive business and if they must operate with one hand tied behind their back, they should be compensated for it.