If you end up using the new equipment and it makes a difference to you, then the answer is yes, you should buy it. This stuff wears out or goes obsolete.
If you are spending more than a few days on the mountain, or you have a season pass, then you should be using modern equipment that can increase your fun.
So the justification is you're you're already committed time and money to have runs on the hill, and you are maximizing fun with the final factor of using good equipment.
An analogy would be like buying an expensive sports car, then saying you can't afford gas to drive it.
I suppose though this depends on your financial situation and what you can afford. If the skis mean you're putting it on credit and eating ramen, perhaps you need to work on your income stream rather then your skiing. I think though in general most people here in general have dispensable income to spend on this hobby.
BTW, you said you ski at squaw/alpine. If you have the pass, then on weekdays you have 50% off demos, which is a very generous perk bringing the price to about $35 with as many swaps as you want. The squaw demo center does have a good selection of demo skis (alpine a little less) , but may not bring them all out until the mountain is better covered (even though they also reserve the right to charge you for damage). Because the last few seasons were so bad, many of the demo skis are basically new.
If you demo, then you can find out whether you are having more fun on the better skis, or if what you really need are lessons or skills improvements.