Expensive balls are worth it to me, but not to the point of paying full price. I go on eBay and buy AAAA Pro-V1's and can usually get them for just over $1 a piece. I just picked up 25 4A Pro-V's for $30. Some you can see have had slight use (no cartpath marks or scrapes), but most look brand new and just have company logos or player markings on them. If you can deal with that, it's a great way to get a good ball at a cheap price. Yesterday I played a ProV that did not have the slightest blemish, looked brand new, but had a FedEx Cup logo on it. Basically a brand new ProV for $1.20.
In the past I have bought a dozen new Pro-V's at the beginning of the year to use as tournament balls and use the 4A's for practice balls, but seeing that there is such little difference between the two I have stopped paying those jacked up prices.