Friends and family get one to use. Another for sites you use credit cards and banking. Another as a junk address for signups at forums, news sites, etc. That way if one ends up getting spammed badly, you can just change it and not affect the others, which is usually the junk address that takes the hit.
If you pay $10 on average for a domain of your own per year at a registrar site and add email services to it, you could have 50 email addresses allowed and that way other than friends and family give each site a unique number up email address, like email@example.com, firstname.lastname@example.org. That also will tell you who is selling your email. You can have all those incoming forward to a single account if wanted for easier use.
I ordered an item through this company through the Cnet Cheapskate. I believe the company above, Xtreme Guard gave my email to numerous internet companies. I had purchased no items for several months before or after. I asked for them to unsubscribe me several times after. I finally sent them a letter this past week asking them to stop the email ads and not to ever send my emails to others. The emails from some of the same companies have started again. I am asking that Cnet alert others about this company, or best quit representing them. This company has a bad privacy statement. There are exceptions to your privacy that favor the company, you could drive a Semi through.