Mostly because they spend the time developing an O/S you want. I bought my first android (fairphone 3) from them, and my next will be from whatever people spend their effords on the firmware (e/os/, iodé, etc)
The major bummer is that Murena only support your phone if you keep the O/S version on it it was sold with. That seems somewhat nuts, but …
Go to https://lowendbox.com/ and click “shop now” under “explore cheap hosting deals” to filter by country. I have Racknerd and Hosthatch (in SE/NL), both of which have been fine for my extremely limited needs.