I'm not a native speaker so take this with a grain of salt. However, I think that the use of the verb form is intentional, and it actually makes more sense to me. For it's not the case that pressing any of those toolbar buttons applies any kind of 'effect' (noun) on the selected objects. Rather, the buttons specify those properties of the selection which scaling or moving should 'affect' (verb). I'm setting the bug status to 'incomplete' to wait for more opinions from other developers or users.
I'm not a native speaker so take this with a grain of salt. However, I think that the use of the verb form is intentional, and it actually makes more sense to me. For it's not the case that pressing any of those toolbar buttons applies any kind of 'effect' (noun) on the selected objects. Rather, the buttons specify those properties of the selection which scaling or moving should 'affect' (verb). I'm setting the bug status to 'incomplete' to wait for more opinions from other developers or users.