I was talking to someone running an ecommerce site, they also run their own lighning nodes and there's many reasons:

- High risk customers that the shop can accept if there's no chargeback option. For these users that are excluded from many ecommerce shops that's a good option and they are willing to jump through some hoops

- Customers from countries that are restricted from using VISA / Mastercard

- People from countries with active sanctions against.

Someone who doesn't have good fiat rails like third-world countries. Or people who just don't want to be part of the fiat system. Or both.

People in other countries trying to buy stuff from US ecommerce sites. A number of payment processors really don't care about them, and simply will not let customers from there buy using a credit card.

Yes, it goes up and down. Fiat currency only goes down. It's a lot more fungible than stocks.

This has tradfi banking ramps. You don't need to hold it. You can treat BTC as basically a payment network instead of something like the visa/mastercard cartel.