Strange subscriptions to newsletter

For the last few weeks I’ve been getting a bunch of really odd subscribers to my website newsletters.
I have a popup on the front page.
The weird part is that some of the names of the subscribers are obviously made up. e.g.
[email protected] Wilbur Looney
[email protected] Alexis Bradford

and there are few others.
Any idea what this might be all about, I don’t see how a spammer could benefit from subscribing to my newsletter.