10% profit is not necessarily very modest. 10% of $50M is a lot of money. 10% of $50K is not a lot of money. 10% only sounds 'modest' in relation to SaaS/software margins which are ridiculous. Walmart's gross margin is only ~28%. Many manufacturing companies compete across 3-5% margins. If the base number is big enough, that's a ton of money still!

%'s are a bad way to measure this, for that reason. Labor isn't even the majority of cost for restaurants (avg is apparently around 34% fully loaded [1]).

[1]https://totalfood.com/busting-restaurant-labor-cost-myth/