Reality dating shows often cast semi-famous people on their shows.
Reality TV dating shows often use people who are somewhat famous for their shows.
この場合、次のような言い方ができますよ。
ーReality dating shows often cast semi-famous people on their shows.
「恋愛リアリティーショーはよくやや有名な人たちに役を割り当てる」＝「ショーにやや有名な役者を選ぶ」
ーReality TV dating shows often use people who are somewhat famous for their shows.
「テレビの恋愛リアリーティーショーはよく幾分有名な人を使う」＝「少し有名な人をショーに使う」
ご参考まで！
カナダ 
