Even if you have an under-provisioned solar+storage solution and don't want to splurge for a generator, even on cloudy days you still get power, just less.

Generally businesses are really great at balancing costs, and for highly-cost-constrained businesses if you give them 95% uptime at half the cost, the equation becomes clear. And in Africa, if the option is 95% uptime or 0% uptime, the choice is even clearer.