A stockbroking firm which takes small orders from clients and takes them on its own account rather than actually transmitting them to the market. Prevalent in the US 1870s to 1920s; often set up as shop-fronts in the 1920s.
A stockbroking firm which sells stock to clients when it has an undisclosed relationship with that company or its owners.
(travel) A travel agency selling discounted airfares, usually in defiance of existing minimum fare arrangements. Now usually refers to any small cheap agency.
A legal services firm selling heavily discounted legal services and documents made in large volume from boilerplate text and clauses, sometimes as a white labelled loss leader.
A company that sells coats of arms associated with the customer's surname, regardless of whether the customer can claim any relation to the original armiger.