Hi There,
Very good question! While you can use any address you like on your own website, virtual offices are expressly forbidden by Google's guidelines. See: https://support.google.com/business/answer/3038177?hl=en The guidelines state:
Use a precise, accurate address to describe your business location. PO Boxes or mailboxes located at remote locations are not acceptable.
While Umar is correct that many companies are violating Google's guidelines, (and, yes, getting away with it!) the problem with doing something you know Google doesn't want is that you never know when consequences may arise. If this were your own business and you were willing to take the risk of a possible takedown of the listing, then it would be a risk/benefit question you would need to carefully consider. It's different when it comes to advising a client. Most good Local SEOs will agree that advising a client to violate a Google guideline isn't the right thing to do. Some folks will argue that they can profit short-term from a guideline violation, and that's likely true, but most clients care so much about their businesses that they are looking for advice that will help them both now and in the future - they want a sustainable marketing strategy.
Highly recommended reading on virtual office takedowns: http://www.localsearchforum.com/google-local-important/26844-busted-warning-attorneys-regus-non-compliant-offices.html
You've asked an important question. It's these types of questions that can help us to be so useful to our clients!