I disagree somewhat.  Back when Circle was in the business of selling bitcoin, I'd made a number of small buys using my checking account, and the next time I visited my bank's main branch I got questioned by the bank manager--not joking.  She asked me what all those transactions were about, and it wasn't like there was a lot of money involved, nor did those transactions represent profits or anything like that.  Banks are very concerned about what you're using their services for, so I would suspect that if you suddenly started depositing lots of money into your account, it would raise a flag with them (depending on the bank, of course; I use a small, local bank).

On the other hand, if you're paying taxes on your profits then the bank can question you all they like and it won't matter much.  Even then, that's not really their business.  But I would certainly expect some scrutiny if you start making "abnormal" transactions.  I even got questioned by that same bank manager about a stock sale check I deposited that was a lot more than I usually deposit.  It's crazy.  You think your money is your own, to do with whatever you like, but they're watching.  Believe me.