What's the deal with the 50$ a month (!!!!) inactivity fee?

For some people who created an account with you to hold for a long term, that might spell very expensive bad news.
Given the mandatory verification, and a mandatory "pre authorized debit" for TD customers (as Vogogo option does not work for them), you simply pave a ground for overly expensive, if not blatantly customer hostile service.
Are you desperately trying to loose your customers?
Where do you see an inactivity fee mentioned? I looked through the 'fees' and 'faq' sections and didn't find it.