I think there are alot of reasons that factor into why this is happening.
1. It's the Jazz. It's not Dallas or Phoenix, I think even Golden State would draw more excitement than Utah. It's not the WCF we were all anticipating. Utah vs San Antonio isn't going to be exciting to the casual fan (which the majority of Spurs fans our, in my opinion).
2. Prices of Tickets. I know there are tons of tickets on Ebay, StubHub, etc. But the original sales of tickets from Ticketmaster, is where the casual fan is going to start. Sorry, maybe some of you can afford $54 bucks for a seat half way up Club 200 for every home playoff game, but I can't. I got a damn good deal on my HD TV that I spent my entire tax return on and I'm going to get a of a lot of good use out of it. I can see the action way better on my TV than I ever could at the ATT, and having friends over is just as good as any playoff experience in an arena (sans The Finals).
3. Spurs PR is . When's the last time we had a "Blackout"? When's the last time they gave away anything we see these teams like GSW, Utah, the Heat, even in Dallas they get clapper thingies! Those maracas were the best thing they ever gave away, they made a of alot of noise and were annoying as but they worked. They brought the arena together and made SA look like a rabid bunch of fans.
4. Prices of The Game Experience. Let's say we spend that $54 per ticket. That's about $120 with taxes and "convenience" charges for two people. Cheapest parking is $8 (I'm not sure if that's still right, I haven't been to a game since last season.) Then if you want a soda or beer that's what like $6 to $7 (so $14 for two people, and that's just one beverage). God forbid you want to eat at the game (easily $25 for two people). And these silly vendors don't even take credit/debit cards for pete's sake! You could easily spend $150-$175 for ONE game. That's ing insane!
5. Gas prices are kicking our asses. With gas being $3/gal alot of people don't have the kind of money to throw down to get to the arena. Getting to work and school usually come first before going to a game for most people.
I love the Spurs to death but if they want to put the blame entirely on the Spurs being "spoiled" or "lazy" or whatever that's there prerogative. I just think they just take these factors into consideration before they go throwing all this blame on us.