We recommend that you use Privacy.com for purchases, with the use of an email address through AnonAddy. This gives you privacy and control related to your purchases that is not easily tied back to you. We recommend that you use AnonAddy as part of a strategy to compartmentalize categories of your email and add a layer of separation from your actual email address, and to use Privacy.com similarly to compartmentalize your online purchasing.
As some examples, you may want to create separate email aliases with AnonAddy associated to online purchasing through websites (and for Privacy.com), one for newsletters (or categories of newsletters), one for people you know and trust, one for people that you may not know as well or trust as much, one for salespeople, etc.
The more ways you can compartmentalize your email and purchasing, separate your identity from your purchases, and erect digital walls to inhibit the ability for other parties to connect your email accounts to you and to any purchases, the better for your privacy. As always, there is some tradeoff between ease of use and the amount of compartmentalization you choose to do. You will need to find a balance that works for you.