Laravel with xampp
The artisan command is just a command line utility for laravel. The serve command just starts up the PHP server.
to run it without artisan you can Configure a server virtual-host (Apache or Nginx) which have the public directory of your project as root directory. Since you are using a MAC I can't exactly instruct you to how to do that.
NOTE
this will help to create the virtual host. but i haven't tried that
sorry i can't comment due to reputation :/ i use lumen (rest api of laravel) with xampp and it works fine. Can you provide somemore details? I also think the path is the problem. Which path you use to access it via a browser? for lumen its /htdocs/project/public/ so in browser: http://localhost/project/public/there i can access the api. should be similar for full laravel project?
Create virtual host and point it to laravel_directory/public/index.php and restart apache.
Creating apache virtual host:http://laravel-recipes.com/recipes/25/creating-an-apache-virtualhost
If you don't want to do that load, localhost/lara_dir/public/index.php
index.php is where all the requests go through.