Have you checked those pages to make sure there are actually links to your site on the referral path page you're seeing in analytics?
If they don't actually have links to your clients sites then it's possible they are just spamming your analytics. There are several ways to exclude this data from your analytics though. https://moz.com/blog/how-to-stop-spam-bots-from-ruining-your-analytics-referral-data
Hope that helps.