For the most part Averted; numerous fanfic/fanart has been created to suggest what happens when Spike grows up (eg: "It Takes a Village"). For the most part, this episode just coincidentally does little to break the fanon treatment of this matter, and if anything, helps to serve it. There's probably a handful of fic and art that are broken, but the creators have said they avoid these elements to prevent them from influencing the show.
On the other hand, the Wonderbolts' presence within easy flying distance of Ponyville is going to wreak havoc on a number of Rainbow Dash fics.
Prop Recycling: The objects in Spike's hoard mentioned under Call Back. It's unlikely that he could have obtained an identical trophy or football from ponies on the street. There's also several other elements seen from earlier episodes (the punch bowl, a scooter that looks very much like Scootaloo's (which he also attempted to take), the kitchen sink, and so on).