Design of rental frock coats - historical precedence?

[salsatron]

Gentlemen,

Just a little question. I've seen pictures of the frock coats that many of the formal wear hire companies have (i.e. Moss Bros, Debenhams etc.), and generally speaking, their frock coats always look like dresscoats with skirts going all the way around the bottom, rather than just limited to the tails - i.e. these frock coats do not close, and the double-breasted buttons are just for show. However, whenever I do actual searches of other sites, the frock coats I see (and this includes any historical photos I find) always show double-breasted frock coats buttoned up. So I was wondering if anyone knew if the rental frock coats are actually based on what has historically been worn, or if they are just modelling them on the dresscoat design for ease of manufacture.

Ta.