[Discuss] Using public DNS for intranet hosts?

[dbarrett at blazemonger.com (Daniel Barrett)]

DNS question: I have a domain (say, example.com). I'd like to assign
domain names to the computers on my home intranet like foo.example.com
and bar.example.com. The names ONLY have to work WITHIN the intranet.

Is it a good idea, bad idea, or neutral idea to use the DNS server at
the *registrar* for example.com to implement these names? For example,
if my registrar is registrar.com, I would create an A record (at
registrar.com) for the name "foo.example.com" that resolves to an
intranet IP address like 192.168.0.15.

This seems like the easiest way to set up these names without
maintaining host files or running my own DNS server (which my spouse
could never fix if I'm unavailable). Is anything wrong with this idea?

I realize that anybody on the public internet can see the name
foo.example.com and attempt to hit it, but when it resolves to
192.168.0.15, they won't reach my server. This is a feature, not a
bug.

Also, from a security standpoint, I don't see that this setup leaks
any information about my home intranet, since nothing in the DNS
record indicates where my home intranet is located.

However, I do wonder whether registrar.com (or other internet gods)
would think I'm trying to hack somebody with this DNS entry.

Thank you,
Dan