Yes, pretty much the same. The difference is where any emails you keep end up. My yahoo emails are on their computer, my comcast or verizon emails are on mine. You manage them the same way.
However, the differences would be apparent when you use them. When I don't log in to my ISP account (let's call it the home account) for a couple of weeks, I have to log in and wait for them all to be downloaded to my computer, then wade through them. If your second account is a Comcast account, that's what will happen.
When my yahoo account has 3-400 messages in it, I just go to the inbox and start deleting them. I had not looked at it for a whole year, but when I did, it was easy to delete all but one message - which was the Pinterest signup message. Now I get three or 4 messages from them every day, but they don't bother me because they are on the other account.
If you do decide to get another account, make sure it does not identify you; not firstname.lastname@example.org, rather some madeup name. In fact, if you used email@example.com....and told us about it - we could email you! And if you used Toy Trumpet for your Pinterest name, we could see your pins....