Of course you could just refuse to sign into these services or opt out of using gmail.
You can still use most of these services without having to link them to an email address/account.
If privacy is really such a worry - why not just do what people have been doing for years with email? Create "throw-away" email accounts to use with google/youtube etc - if you truly are paranoid, create a new account every 48 hours. It's a bit overkill, but your privacy concerns are safe when google is unable to associate them with any person that exists for more than a day or two.
Of course I don't have anything to hide regarding my activities online - and if google can locate even better prices for things that I am interested in, then great! The decision to purchase or delete still remains with me.