פירוש על עבודה זרה 88:14

Rabbah b. Ulla has yet another answer as to how Rabban Gamaliel’s response may have been deceptive. Rabban Gamaliel claims that people do not say that the bathhouse was made for Aphrodite. But, Rabbah points out, even if they did say this, it still would not cause the bathhouse too become prohibited because items cannot be dedicated to idol worship. Even if they are, they are still permitted.
But Rabbah b. Ulla says that the remark was not actually deceptive. While we would not consider the bathhouse to have been dedicated to idolatry, it still would have been prohibited as an ornament for idolatry. Thus Rabban Gamaliel needed to point out that it is not prohibited because the idol adorns it; not the other way around.