That's because . is a method call, + is addition, and comma is a list separator. Which of those would you give up? So yes, the ~ is a little unique to Perl6, but at least they were thoughtful enough to pick something with more than one easy mnemonic.
I guarantee you, most people new to the language would be much more put-off by keeping perl5's -> for method calls. Perl lost that battle, it's over. They're making the best of it.
Also, any language with a self-reflective object system is going to show that off to beginners to help them explore, even if it wouldn't be used in production code much. That's like complaining about a language tutorial showing off the REPL to start out, even though you don't use it in production code.
I guarantee you, most people new to the language would be much more put-off by keeping perl5's -> for method calls. Perl lost that battle, it's over. They're making the best of it.
Also, any language with a self-reflective object system is going to show that off to beginners to help them explore, even if it wouldn't be used in production code much. That's like complaining about a language tutorial showing off the REPL to start out, even though you don't use it in production code.