With users that use commercial features without paying for them.

It is quite easy to know which features those are when they require a flag named -XX:+UnlockCommercialFeatures, you just don't use them by mistake.

Oracle gives free license to use commercial features in development[1] in section B. It is very easy to some script for JVM startup parameters and get that script deployed in production by mistake.

1. http://www.oracle.com/technetwork/java/javase/terms/license/...

Quite right, but unless I am too cynical I doubt those deployments were actually done by mistake, when I relate how many companies try to "alleviate" their costs.