Actually I was reading something about how Disney has dialed back the anniversary celebrations partly because they had gotten to making such a big deal out of them, that these "celebrations" were actually starting to be diluted to the point that guests weren't interested in them. As such, they've made an effort to really keep them on a smaller scale, with the intention to look forward to making a HUGE deal for the 50th anniversary in 2021. So, they keep the celebrations to smaller in park celebrations on the day of.