I disagree as to the bogosity of this practice.
There is nothing wrong with adding clarity to a statement that may otherwise be confusing or ambiguous. And there is nothing wrong with reducing the number of rules someone needs to know in order to correctly decipher a statement.
This is just such a case, because an argument given to print can start with either a filehandle or a variable. Depending on what follows, it can be very hard to tell which is intended without braces.
I do enjoy how Perl lets one push the boundaries of acceptable syntax, but that doesn't mean it's always a good idea to do so. That's just my opinion, of course.
When's the last time you used duct tape on a duct? --Larry Wall