Historically, many companies, from Wordstar (OK, Micropro) to Microsoft have built huge installed base from pirated copies.
A large company likes piracy for a number of reasons. The most obvious is that it builds an installed base and makes the software a de facto "standard." You could probably more properly say that it makes the file format a standard. You saw that yourself with your experience with DocX. Microsoft would rather you use a program that defaults to DocX, paid for or not, than to have you use another program that supports DocX but defaults to something else.
If they catch you with pirated copies, particularly if you are a business, they have leverage to force you to buy more of their software. Just because they *want* you to pirate does not mean they will *forgive* you for it. :) BSA, the enforcement arm of Microsoft, has often used this technique to force companies who have been whistle-blown to sign exclusive purchase agreements with Microsoft, along with hefty fines.
Yeah, I know BSA is an "industry group." It's still the piracy enforcement arm of Microsoft.
In the old days, some companies have used "amnesty programs" to get pirates to come in from the cold and get legal. Wordstar kick started its Wordstar 2000 product by giving a deal to anyone who had a previous copy of Wordstar, legal or not.