Freshping is a pinging service similar to UptimeRobot in the sense that it gets the website status of a site (and in the process wakes them up).
Like most pingers, when FreshPing pings a server, it sends a custom user-agent so that that the server can know that it is FreshPing.
Now that we’ve got the who and what, let’s think of theories of why it’s blocked.
I kinda agree with NNBP - perhaps people tried to add Replit to FreshPing which accidentally caused a DoS attack? I’m not really sure of the details. As for why it follows robots.txt - no clue whatsoever to why the devs decided to do that.