Great insight from MacSparky on the recent Uber / Unroll.me controversy:
Free is never free. Indeed in this case, where unroll.me is owned by an analytics service, it appears that the entire purpose for the service is to get access to user email data for monetization. So apparently Unroll.me, with access to its user email accounts, collected their Lyft receipts, anonymized them, and sold them to Uber. I'm pretty sure people signing up for unroll.me don’t expect that to happen.
I was an Unroll.me user until this story broke. Even though I knew the service was free and that I was probably paying for it with my data – It was easy to forget once the service became an integral part of my workflow.
I have since signed back up for Sanebox (I should have just stayed all along instead of trying to save a few bucks). It's reassuring to know that, with Sanebox, I won't be the product because I'm paying for the product.
Source: Free is Never Free — MacSparky