On one hand I think 110 (after fees) for the floor is a bit much and 130 for loge (before fees) is too much. I base part of this on personal experience. In '85 I attended the 20th anniversary shows at the Greek. $15/per, GA. In terms of inflation/cost of living, how does that equate? You do the math.
I think a gallon of gas back then was just over $1. A six pack of Heineken was $4-5. From that standpoint a Furthur ticket at the Cap proportionately is higher. Now a ticket at Boardwalk by those measures is a good deal.
Why did they choose to play the Cap instead of another larger venue that would allow a less expensive ticket price? I suspect partly the output of support from people on this forum (and elsewhere) that wanted to see them there. Also, I hear in it's remodeled state it's a very nice venue. Another point to justify this was more nights played equals more nights people have opportunities to see them vs. 3-4 nights Radio City or 1-2 nights at the Garden. However an extended run reduces labor costs considerably (1 day to load in, 9 shows, load out night of last show) as opposed to playing 3-4 venues in the same time frame.
As far as what other acts charge it doesn't matter to me. $200 for the Stones? If you offered me a free ticket and they were playing across the road I might consider. As far as musical quality Furthur is by and large a good value overall. And I'm hesitant to say but there are a very finite number of shows left for us to have the chance to see, which factors in to my decision to pay a little more.