The lack of a charger comes partly from an EU measure. They essentially don't want huge numbers of unnecessary chargers made and sold while passing that cost to the consumer. On that basis they think you should be able to use the existing charger you have or buy one separately to suit your needs.
This is actually a good move overall. You are paying for the charger when you get it with your phone, you just pay more for the phone. They made it a requirement that devices have a USB C port for charging so they are all compatible. That means if you like fast charging you can get a charger which supports that and suitable cables. If you prefer lower charging speeds and want a longer cable you can do that instead. Or if you want to exclusively use wireless charging you can do so too.
I personally have not found the chargers from phones to be of good quality, mostly they were just barely passable.