I think there’s some confusion on what malware and viruses are.

Malware is the general category of malicious software and includes viruses. Nowadays anti-viruses are actually anti-malware, and it’s generally preferred to always refer to malware instead of viruses, viruses are in fact very rare.
Being ‘for profit’ is not part of neither definitions.

Source: http://en.wikipedia.org/wiki/Malware

Malware, short for malicious software, is software used to disrupt computer operation, gather sensitive information, or gain access to private computer systems.[1] It can appear in the form of code, scripts, active content, and other software.[2] 'Malware' is a general term used to refer to a variety of forms of hostile or intrusive software. (...)

Malware includes computer viruses, ransomware, worms, trojan horses, rootkits, keyloggers, dialers, spyware, adware, malicious BHOs, rogue security software and other malicious programs; the majority of active malware threats are usually worms or trojans rather than viruses.

I hope that clarifies.

The most useful part of avast on the mac is actually the web protection, and actively blocking malicious sites, this is the major attack vector, and takes advantage of browser vulnerabilities still unpatched.