THE SOLUTION:
There are 24 possible mixes of products giving a total of 81 possible combinations, as follows:
Don, popcorn – Jon, popcorn – Lon, popcorn – Ron, popcorn
Don, popcorn – Jon, popcorn – Lon, popcorn – Ron, peanuts
Don, popcorn – Jon, popcorn – Lon, popcorn – Ron, nachos
Don, popcorn – Jon, popcorn – Lon, peanuts – Ron, popcorn
Don, popcorn – Jon, popcorn – Lon, peanuts – Ron, peanuts
Don, popcorn – Jon, popcorn – Lon, peanuts – Ron, nachos
Don, popcorn – Jon, popcorn – Lon, nachos – Ron, popcorn
Don, popcorn – Jon, popcorn – Lon, nachos – Ron, peanuts
Don, popcorn – Jon, popcorn – Lon, nachos – Ron, nachos
Don, popcorn – Jon, peanuts – Lon, popcorn – Ron, popcorn
Don, popcorn – Jon, peanuts – Lon, popcorn – Ron, peanuts
Don, popcorn – Jon, peanuts – Lon, popcorn – Ron, nachos
Don, popcorn – Jon, peanuts – Lon, peanuts – Ron, popcorn
Don, popcorn – Jon, peanuts – Lon, peanuts – Ron, peanuts
Don, popcorn – Jon, peanuts – Lon, peanuts – Ron, nachos
Don, popcorn – Jon, peanuts – Lon, nachos – Ron, popcorn
Don, popcorn – Jon, peanuts – Lon, nachos – Ron, peanuts
Don, popcorn – Jon, peanuts – Lon, nachos – Ron, nachos
Don, popcorn – Jon, nachos – Lon, popcorn – Ron, popcorn
Don, popcorn – Jon, nachos – Lon, popcorn – Ron, peanuts
Don, popcorn – Jon, nachos – Lon, popcorn – Ron, nachos
Don, popcorn – Jon, nachos – Lon, peanuts – Ron, popcorn
Don, popcorn – Jon, nachos – Lon, peanuts – Ron, peanuts
Don, popcorn – Jon, nachos – Lon, peanuts – Ron, nachos
Don, popcorn – Jon, nachos – Lon, nachos – Ron, popcorn
Don, popcorn – Jon, nachos – Lon, nachos – Ron, peanuts
Don, popcorn – Jon, nachos – Lon, nachos – Ron, nachos
Don, peanuts – Jon, popcorn – Lon, popcorn – Ron, popcorn
Don, peanuts – Jon, popcorn – Lon, popcorn – Ron, peanuts
Don, peanuts – Jon, popcorn – Lon, popcorn – Ron, nachos
Don, peanuts – Jon, popcorn – Lon, peanuts – Ron, popcorn
Don, peanuts – Jon, popcorn – Lon, peanuts – Ron, peanuts
Don, peanuts – Jon, popcorn – Lon, peanuts – Ron, nachos
Don, peanuts – Jon, popcorn – Lon, nachos – Ron, popcorn
Don, peanuts – Jon, popcorn – Lon, nachos – Ron, peanuts
Don, peanuts – Jon, popcorn – Lon, nachos – Ron, nachos
Don, peanuts – Jon, peanuts – Lon, popcorn – Ron, popcorn
Don, peanuts – Jon, peanuts – Lon, popcorn – Ron, peanuts
Don, peanuts – Jon, peanuts – Lon, popcorn – Ron, nachos
Don, peanuts – Jon, peanuts – Lon, peanuts – Ron, popcorn
Don, peanuts – Jon, peanuts – Lon, peanuts – Ron, peanuts
Don, peanuts – Jon, peanuts – Lon, peanuts – Ron, nachos
Don, peanuts – Jon, peanuts – Lon, nachos – Ron, popcorn
Don, peanuts – Jon, peanuts – Lon, nachos – Ron, peanuts
Don, peanuts – Jon, peanuts – Lon, nachos – Ron, nachos
Don, peanuts – Jon, nachos – Lon, popcorn – Ron, popcorn
Don, peanuts – Jon, nachos – Lon, popcorn – Ron, peanuts
Don, peanuts – Jon, nachos – Lon, popcorn – Ron, nachos
Don, peanuts – Jon, nachos – Lon, peanuts – Ron, popcorn
Don, peanuts – Jon, nachos – Lon, peanuts – Ron, peanuts
Don, peanuts – Jon, nachos – Lon, peanuts – Ron, nachos
Don, peanuts – Jon, nachos – Lon, nachos – Ron, popcorn
Don, peanuts – Jon, nachos – Lon, nachos – Ron, peanuts
Don, peanuts – Jon, nachos – Lon, nachos – Ron, nachos
Don, nachos – Jon, popcorn – Lon, popcorn – Ron, popcorn
Don, nachos – Jon, popcorn – Lon, popcorn – Ron, peanuts
Don, nachos – Jon, popcorn – Lon, popcorn – Ron, nachos
Don, nachos – Jon, popcorn – Lon, peanuts – Ron, popcorn
Don, nachos – Jon, popcorn – Lon, peanuts – Ron, peanuts
Don, nachos – Jon, popcorn – Lon, peanuts – Ron, nachos
Don, nachos – Jon, popcorn – Lon, nachos – Ron, popcorn
Don, nachos – Jon, popcorn – Lon, nachos – Ron, peanuts
Don, nachos – Jon, popcorn – Lon, nachos – Ron, nachos
Don, nachos – Jon, peanuts – Lon, popcorn – Ron, popcorn
Don, nachos – Jon, peanuts – Lon, popcorn – Ron, peanuts
Don, nachos – Jon, peanuts – Lon, popcorn – Ron, nachos
Don, nachos – Jon, peanuts – Lon, peanuts – Ron, popcorn
Don, nachos – Jon, peanuts – Lon, peanuts – Ron, peanuts
Don, nachos – Jon, peanuts – Lon, peanuts – Ron, nachos
Don, nachos – Jon, peanuts – Lon, nachos – Ron, popcorn
Don, nachos – Jon, peanuts – Lon, nachos – Ron, peanuts
Don, nachos – Jon, peanuts – Lon, nachos – Ron, nachos
Don, nachos – Jon, nachos – Lon, popcorn – Ron, popcorn
Don, nachos – Jon, nachos – Lon, popcorn – Ron, peanuts
Don, nachos – Jon, nachos – Lon, popcorn – Ron, nachos
Don, nachos – Jon, nachos – Lon, peanuts – Ron, popcorn
Don, nachos – Jon, nachos – Lon, peanuts – Ron, peanuts
Don, nachos – Jon, nachos – Lon, peanuts – Ron, nachos
Don, nachos – Jon, nachos – Lon, nachos – Ron, popcorn
Don, nachos – Jon, nachos – Lon, nachos – Ron, peanuts
Don, nachos – Jon, nachos – Lon, nachos – Ron, nachos