It's a temporary inconvenience; look at it rationally. They have (I think) five parking lots on west campus. Even if they want to replace those with structured parking, they'd have to close those lots while they construct garages on them.
People have been coming to the games in relatively large numbers for over thirty years (well more than that if you consider crowds of 35,000-40,000 at Archbold). There was never any more parking in that neighborhood than there was up through last year, when apartment construction on the first block began. Somehow people managed to get to the hill, even when there was less parking in the neighborhood than there will be next fall.
Further, while I know that the tailgating space is very important to everyone, keep in mind that these are the lots that many on this board have repeatedly disparaged for their inaccessibility. Several times in recent months we've seen hue and cry about the 40-minute traffic back-ups leaving those lots. More than a few have noted that those permit lots are the worst option in terms of accessibility.
It's not crazy that SU wants to construct more buildings on land it owns, and it's sure not crazy that it wants to beautify the ugliest part of its campus. They're doing the best they can.