"looking in" and "making out"

Posted by Miri Barak on November 03, 2004

Hello dear friends:

I cite the whole passage but need help only at the end of it:
"An ultimate beauty car will create desire, provoke emotion and in 50 years time still leave people agog. Often utilising the newest technologies to dress their awesome performance, *these are the cars that get steamy windows from looking in, not from making out*.

It's a sort of pun, but I did not understand it: what does he mean by looking in and making out, and what is the connection to steamy windows?

Thank you so much