Yes, this is a thing. Some people that are making their first steps from the Windows world to Linux often ask and install antivirus software on to their setup without knowing that this is often pointless and a waste of their system resources.
There are many factors that help prevent malicious software running on a Linux system that make running a antivirus package useless.
First, because there are so many different distributions of linux that have different structures to the core of the operating system, it is near impossible for a coder to target a large enough audience. While, for example, Ubuntu is growing, even Ubuntu has so many variations that seperate it in layers that make it impossible for crackers to develop for.
Secondly, the structure of the multi-user environment require that privileged users are the only users to have access to core software and kernel space. And for this privilege to be grant to just any software in Linux is rare.
With the popularity of some distributions Linux growing, the concept of an app store or Software marketplace is a must. These online sotres means that software is checked and published ensuring that the software is safe for use and not harmful, keeping the end user from accidently install malicious software.
Last, this article by blogger HTG explains further why Antivirus on Linux is not entire necessary.
If you have any thoughts or questions on this topic, please leave a comment below.