I think some of you are overthinking this. There are a few reasons why someone may prefer a prepaid card overseas versus a 'regular' credit card. It makes it easy to budget and also affords a level of protection since your maximum exposure is the amount loaded on the card.

I went through the process of signing up for one because (1) it's free and (2) it's easier for me to talk about things I've experienced than draw conclusions based on guesswork

Buying $100 USD on the card is $0.11 CAD cheaper than doing a simple forex purchase via TD's online banking service. Plus the money you load onto a card can come from another credit card that collects points.

So, to summarize:

1. it can be safer than a regular credit card
2. it's easier to budget -- similar to carrying cash since you can only spend what you have
3. it saves me at least 2.5% in forex fees (I don't have any of the Chase cards)
4. I earn rewards from the credit cards I use to load the card
5. the app is straightforward and load-ins & transfer are instant

This really isn't such a bad product for someone who wants to or needs to spend multiple currencies without carrying a wad of local cash and doesn't have a no-forex fee card.

Edit: just saw segacs' post above. I guess I'm a fool who doesn't know anything about personal finance.