The title "Toys in the Attic," of course, predates both henryclem's and Bon Jovi's songs ~ it's the title of a Lillian Hellman play.

Once a catchy phrase like enters the public arena, it's likely to inspire a song, and the songwriter might very well appropriate the title without conscious knowledge of where the phrase came from, how it entered his/her head.

That's probably one way that new songs come to be named with previously-used titles.

The song titles that I find most intriguing are those composed of words that appear nowhere in the lyrics. Dylan did that pretty frequently, especially in the late 60s: "It Takes A Lot to Laugh, It Takes a Train to Cry," "Temporary Like Achilles," etc. Weird off-the-wall titles like that are very unlikely to be used again by other songwriters...