DeletedUser31540
I slightly disagree with this. I'm glad they usually offer less-than-stellar prizes in the last few hours so I don't have to worry about saving up event currency for a mad rush at the end. As it is I had a fully upgraded train, with an extra level 1 and a couple of extra upgrades, by the next-to-last day. That's not to mention all the stuff I got apart from WT stuff. I spent diamonds by the fistful on this event just to get enough expansions to fit all my train cars. By the last hours of an event there's nothing else I need or want, or have room for.
If a prize is good enough (power creep) there will always be room for it (by deleting outdated and less efficient structures)