There are a lot of free services. Sure, they are getting money from someone, but small personal accounts often are free. Like they hook me on free account and then I recommend it or upgrade as I grow or just spread information about it. For example I never paid for DNS hosting. Currently I'm using Cloudflare for free.
> With free email (gmail) the payment is not direct. They are doing something to get money, but what is unknown.
I guess you mean something uknown and nefarious.
And you are more comfortable with Qihoo 360, the Chinese company that owns Opera/fastmail?
FastMail hasn't been part of Opera for over 5 years now, since well before Qihoo bought most of what was left of Opera: https://fastmail.blog/2013/09/25/exciting-news-fastmail-staf...
I use fastmail because the payment is direct: I give them a few bucks each month.
With free email (gmail) the payment is not direct. They are doing something to get money, but what is unknown.