A side effect is that it allows anyone running a website to build a database of TeamViewer installs behind IP addresses. If there was a TeamViewer security issue, that database could be useful.
_Any_ website can tell whether or not you have TeamViewer installed. Ad networks could theoretically target you based on whether or not you have TeamViewer installed.
I’m not assuming malice, but it’s a much bigger privacy hole than just increasing fingerprinting by a few bits.