I agree with your though. But looking at design of base_format, get_format_options() return empty array, if format doesn't have any options.
Saying so, such case should be handled by calling method (in this case section block). As course_format_options() or section_format_options() are not abstract, it's upto course format to implement it. With your patch it will fix the problem for social course format, but it might be an issue for custom course format.
If you have another patch, then feel free to post it here and I will be happy to replace the branches.