None of which however, I would argue, is quite as off or wrong as it seems.
Passover is a holiday celebrating, among other things, the coming of spring again and all that means: renewal, warming, hope, trying again/anew/some more. That is what the start of baseball season is about too so a baseball chip and dip plate fits right in. Spring itself comes not on schedule -- here in Seattle we had our first (and hopefully only) snow flakes of the the year on the first day of spring. So scheduling these things give or take a week seems appropriate too.
Passover is a holiday celebrating, among other things, storytelling. This is my kind of holiday. What's important is the telling and retelling of a story which is at once ancient, timely, and timeless. So being off calendar by a couple weeks seems small potatoes.
Passover is a holiday celebrating, among other things, homecoming. Some years that's more of a process than others. The years, such as this one, when that process is most protracted are the years it is both hardest and most important to do a seder, however belatedly. When I was in college, we used to schedule Passover for whenever I was home for spring break. I still don't feel quite moved in, quite home or at home, but this helps.
Passover is a holiday celebrating, among other things, symbolism. Again, this is something I can get behind. Except for the shank bone. Not eating meat makes procuring a shank bone a challenge. Also, it is gross. Careful observers will note the dog treat -- the only bone-shaped or bone-inclusive item we had on hand -- in place of a shank bone on the baseball seder plate. Dogs celebrate homecoming and spring-coming too you know.