The best part about that horrible dialog is that I have to lie to it to make it go away. I'm okay with using my real name but I am NOT going to make a G+ profile to be allowed to use youtube.
Especially in the chance it starts publishing anything about my youtube usage.
As I recently discovered, having a youtube account is synonymous with having a youtube 'channel'. And if you use the 'favorites' feature of the youtube mobile apps while logged in (thinking, perhaps innocently: "how convenient to save this video I was emailed until later, when I have a larger screen available.") you may be interested to know those favorites are displayed on your publicly-accessible channel page by default.
Especially in the chance it starts publishing anything about my youtube usage.