> it was probably not a successful business.
yes, that is exactly the anti-union rhetoric: if you form a union, we can't continue business and you will lose your job.
Restaurants have famously thin margins. If the profit margins are 5%, then a 1% increase in expenses (due to union demands) results in a 20% reduction of profits.
Unions can drastically increase operating costs for a business. When I was at a trade show in las vegas a few years ago, I had to work with a "lighting guy", "setup guy" and a "cleaning guy" to plug in a couple lamps for our display, b/c each role was unionized.
The problem with profit margins is that they're often artificially low in order to fuel business expansion, which may not be necessary.
I actually managed restaurant business. Our labor cost target was 15%, and food cost 30%. Then operating expenses like electricity, water, rent... I'd estimate there's 20% of revenue left over. Was our profit margin then 20%? No, because we were constantly buying new stores and random things we don't need. For example, a 16,000 dollar automated flattop grill that barely works, when we already have a flattop.
I'm often dubious of the "capital" that businesses purchase. Point being, profit margins are not really a good measurement of much. I can burn money and have low profit margins, if I wanted.