you should use one route but use mkt and crm as a variable.
contact:
path: /{ prefix }/contact
defaults: { _controller: YourContactBundle:Contact:contact }
Then in twig or wherever you want
{{ path('contact', { 'prefix': prefix } ) }}
You should retrieve the variable contact by session or by giving parameters to the route.
As it's just some few bundles who are in common, i would recommend to give the parameter.
In home of the market app, i would call the contact form by {{ path('contact',{ 'app_prefix' : constant_prefix_mkt} ) }}