Why are some football clubs known as Wanderers?
There is a blog entry from the Oxford Dictionaries addressing English football club names. It's newer than the original question. The following explanation is offered for the clubs named Wanderers early on.
The names Wanderers, as in Wolverhampton and Dundee, and Rovers, as in Bristol and Raith, were adopted by teams without a permanent home ground. - ODO Blog
Everyone named Wanderers who adapted the name later on is as likely as suggested in the comments on the imitation train.