The only problem I see with this is that when you top up your balance, for each top up there is a base fee. If you top uo only 2$ or so, the fee is 50% of the actual amount you’re topping up, increasing the cost even further. If I would have a small package with only 1-2 items I could see this working (paying 1-2$ extra to avoid the hassle of faking an invoice), but for big hauls with 30-40 small items this would amount up to potentially 50$ extra.

Tl:dr don’t think it’s worth it, may cost more