Multiple Industry Solutions on a single C4C tenant

The question is whether it's possible to enable more than one IS on a single C4C tenant (or an IS alongside the standard solution.) SAP does not provide a clear guidance, so by being mum on the issue it's implicitly confirms that multiple IS's could be enabled on a single tenant. Is it true or not?

Here's the use case I have ran across: an IS Utility customer also wants to enable the consumers of its electricity services to use Shopping Cart functionality to buy physical products (like thermostats, meters, etc.) using the Shopping Cart functionality available in IS Retail as of 1508. Another use case is to use a single training tenant for displaying abilities of multiple Industry Solutions of C4C

Please, share your opinions or the actual experience on this topic.