Perl is actually more in the "real language" camp, believe it or not: It makes it more verbose to launch other programs than to not launch them, and it doesn't have pipes.

In a shell, any bareword is either one of a few built-ins or an external program. Using a bareword which doesn't correspond to anything isn't a syntax error, because the parser can't know what programs you have installed from moment to moment. That is the biggest difference between a shell CLI and a programming language REPL.