Can a hyphen be used without anything on the right side?
The Chicago Manual of Style advises:
When the second part of a hyphenated expression is omitted, the hyphen is retained, followed by a word space.
The hanging hyphen sets the reader up to expect a series of hyphenated expressions, all of which have the same second part. If you omit the hanging hyphen, therefore, it's not clear that the series has begun until it is already over, which may force the reader to go back and re-read the sentence for clarity.
It's also consistent with AP style (Associated Press Manual of Style) to use a hyphen and space when part of a compound modifier is omitted, as shown in previous answers (in constructions such as "The restaurant offers both left- and right-handed utensils.")