Bronte - it sounds to me like it is not 'free' time to be spent on other endeavours, but 'under-utilised' time to work on initiatives to support the core business.
If there are no customers physically walking in, or that can't be coaxed in through sales/marketing initiatives, then here are some ideas she may consider (please forgive me if I am way out, but I don't know the exact type of business - am assuming something retail like a gift shop or fashion store etc.):
- utilise some methods to level out demand to fill the troughs: alternative product offerings; change range of stock on a more frequent basis to create fresh/surprise look; develop complementary service offering (e.g. repairs/ rework/ after sales support such as follow-up communication or offers to existing customers/ sell insurance or financing options...)
- go down the "experience" route in the store which may keep existing customers there longer (provide coffee area; internet access...)
- develop web site, and sell from that. Utilise spare time maintaining the site, and running operations from it;
- 'insource' as many activities as possible. For example, is she outsourcing her accounts? Perhaps paperwork, accounts, budgets etc. can be done at that time?;
- spend time focusing on backend activities (non-sales), which might reduce cost, e.g. better sourcing, negotiation with existing suppliers, tranportation/distribution cost management...
- share capacity with related businesses in the area (common stock areas or maybe they all share off-peak sales times and can pool sales staff?)
- read around the topic. Some good ideas on this site: ... in paricular, the Zara case study Retail @ The Speed of Fashion: Case Study