How is paying $20 instead of $50-60 ripping themselves off? Have you considered that the extra 985GB might be useless to them?

I'm paying $15/mo. To pay $50/mo for in the end the same thing (I'm going to use the same amount of data regardless) just means I'm spending $420 a year more for the same outcome.

How is it a better deal to spend more money for essentially the same thing?

Imagine you're buying food that will go bad tomorrow. You can't keep it. You can't share it. You can buy enough food to fill you up today for $5, or enough food to fill you up 50x for $20. You will still eat that one unit of food, the other 49 units will just go to waste. Which do you buy?

For all the time I've had Mint, I've saved nearly $3,000 compared to your $50/mo plan. I've never felt the urge to really need more data personally, and it's worked well for me on my international travels around North America. If the outcome was the same, wouldn't you rather keep $3k in your pocket?