SEO spam results on Google embedded through legit websites?

See this specific google search:

https://google.com/search?q=ostereiermarkt+bhattacharya+paznokci

the query keywords are unique and distant enough to only get the spam results

So for example this website https://nagoya.nikke-tennis.jp/ appears to be a legit website about a tennis court in Japan.

But google has indexed it as

ht tps://na goya.ni kke-ten nis.jp/?wptouch_switch=desktop&redirect=//entecaby.ml/b80nagoyanikke-tennisjptA8400

(obviously without the randomly added spaces to avoid anything from opening the link)

So I assume a lot of these websites are really legit, but has been hacked to serve spam as well? I guess it works because it rides on the existing website's reputation. A little bit parasitic in a way.