Surprised to see these for sale

That is the common dandelion according to the latin name. I dont think there's a catch. I'm guessing they sell enough to make it worth packaging them. I cant see them having any problems cultivating them.
My guess is they may be mainly bought by people who live in flats who own tortoises to grow as a treat if they dont want to be labelled as the odd bloke who picks dandelions from the grass verge.