The reason why I am saying this is that the stem is positioned in such a way to balance the jug. If you imagined a line through the middle of the opening of the jug, it is clear to see that the handle lines up with the stem of the base. Everything is central.
If the foot was applied first, then obviously a trainee would be expected to position it so that the jug balances. The addition of the handle wouldn't make much difference to the balance.
The reason I keep coming back to the 'practice' explanation is the fact that the handle and foot are a clear mismatch; they are completely out of character with base shape of the jug.
If this were a production piece, then another way to identify it would be the 'hammer' handle. It's an unusual design and I haven't seen anything like it before. Similarly I haven't seen a foot applied in such an awkward manner either. If someone else can find a similar example then you may be on the way to making an identification.
When it comes to some of the more outlandish Victorian glass, or scientific or industrial glass instruments, there are some parallels, but the main shape of the jug doesn't fit that possibility.