37Signals could probably do it some other way but this was the most convenient way for them it seems. They probably do it for the same reason we do: easy to di

37Signals could probably do it some other way but this was the most convenient way for them it seems. They probably do it for the same reason we do: easy to direct traffic to different DBs and VMs this way, instead of waiting for the request to come in and direct it some other way. There might also be an added value to the business/account seeing their name in the url... Not sure about that one though.