Waas passed away on 19 April (16) at Abington Hospice in Warminster, Pennsylvania according to Billboard.com.

In the 1950s, Waas founded his own advertising company, Waas Inc., and went on to write a tune which later became synonymous with Mister Softee ice cream trucks in the U.S. The 1960 song has been featured in Larry David's Curb Your Enthusiasm show and Bernie MAC's 2004 film Mr. 3000.

It was also recorded by American thrash metal band Nuclear Assault and composer Jed Distler, who based his String Quartet No. 1: The Mister Softee Variations, on the track.