They absolutely do! If you purchase their Zing JVM, it is generally because of the very low GC pauses it brings. And after that occurs, you quickly start to notice what other things are going on on your system to cause unwanted pauses in your processes.

In order to effectively sell the JVM, they need to help you understand and reduce the non-GC pauses so you can realize the full value of your investment.

(full disclosure: happy Zing customer)