At 42 locations, I doubt this chain has the capital to automate the restaurants with the technology currently available.
It should be interesting and informative to watch this unfold. At this scale, all of the bad things that a union can inflict on the company, the workers and the customers should unfold pretty quickly.
On the other hand, the newly formed union may become a target of acquisition by a real union, such as the UFCW. The company executives will start singing a different tune if that starts happening.
The Teamsters or the Mine Workers would be my choice.