Open Source exists, but it is janky, lacking in features, and literally every single one is used to upsell the expensive proprietary software by the same company that has the features lacking in the open source release.
Restaurant owners would care about open source, if the offerings weren’t expensive to implement. See my comment on the same level.
I meant more that a restaurant owner isn’t going to see or really get any value from an open source solution vs closed source specifically. They are just choosing a platform at a price point that works for them.