2 years ago I was checking in to the Ritz Montreal using my company code and was asked for company ID as I was booked under a corp code. I produced my business card,passport and credit card and was told that wasn't a company id and I need to prove I worked for the company, when I informed the clerk that my company doesn't issue ID's and hasn't done so for 5 years she told me I might have to pay rack rate as a result. I directed her to search the internet for my name and company name which produced a landing page with my title and picture on the company website & she printed to use as proof I was an employee. This was the first and only time I have every been asked to prove I worked for the company when checking in.
Two weeks ago I checked in to the same hotel using the same discount and no-one challenged me.