Paris, TX had a defunct billiard supply a few years back. The former owner had bought and renovated the house behind his and tried to turn it into a residential-area billiard supply with a yellow pages ad that said 'by appointment only'. The shelves were stocked, sort of, but some of the liquid products had an odd feature - during the many years sitting on the shelf, they liquid contents had completely evaporated, and the owners didn't even know it.
I bought some mid-level balls. I thought were new in the box, but when I got them home I saw a lot of strike marks on every ball, and realized they had been used quite a bit as demo balls on the tables in the store, later in the residence.
I would not ever buy any more balls except first-line Aramith or, at some point, maybe Centennials because I like the way Centennials look. There is just no percentage in having any balls except the best. Balls are not so different I think at the lower price levels.
Maybe when the lottery pays off I might spring for a good set of old mud balls to go with an old fuzzy cloth table, just to see how they played in the good ole days. I'll probably never get Cyclop balls, nor any TV colored Aramith balls, because I don't want any puke or puce colored pool balls.