The Messenger of Allah ﷺ got him self cupped and gave the cupper his wages. Had he considered it impure, he would not have given it (wage) to him. (Using translation from Abū Dāʾūd 3423)
«احْتَجَمَ رَسُولُ اللهِ ﷺ وَأَعْطَى الْحَجَّامَ أَجْرَهُ وَلَوْ عَلِمَهُ خَبِيثًا لَمْ يُعْطِهِ»