I do not remember to see/visit ANY American steakhouse that did NOT brag about how they slowly (24-48 hours) tenderdize, cure, etc. their meats. As bevbme mentioned they usually get the meat already tenderdized. So it is possible that they told you the true, they do not ADD anything more. But there was already more than enough in the meat. Similar way, most of the restaurant use frozen half-prepared vegetables. And they do not ADD anything more.

Maybe this is some kind of food safety issue?

Maybe some smaller family owned restaurant has real fresh steak, but I have never seen them here, in US.