If it's malicious, that is, changes things without express consent, then it's malware. No debate. End of story. Malware is a parasite.

Crapware is something that's installed and shows up on your desktop, may even start automatically and produce pop-ups all the time, but doesn't alter the behavior of other applications. It's just junk, but it's not inherently detrimental or damaging. Crapware applications are barnacles.