Here is a OverPass query for finding hotels and similar establishments claiming that they have internet access. According to internet_access it should not really be tagged, although the same wiki mentions option of using “internet_access:fee=customers”.
( tourism~/(hotel|motel|chalet|guest_house|hostel|apartment|resort)/ ) && ( internet_access:fee=* || internet_access=* ) && internet_access:fee!=customers