I don't think Universal cares about making sense!
To be honest, I see pros and cons for both.
Like I said, while having IOA for EE gives people a chance to get in there sooner and have more people ride it perhaps before the regular guests come into the park, it eliminates the chance of regular guests who been waiting outside of the park to get there early to lessen there chances of waiting forever to get in, only have to wait insane lines since EE guests got there first.
Where as having USF for EE makes everyone have to wait even longer to get on Hagrid's coaster which will increase crowds outside and queues for HE, but at least EE has a choice of waiting, or enjoy half of the park before focusing on Hagrid's coaster once IoA is open.
Obviously one option favors for a particular type of guest and while having an extra hour to have some people to ride Hagrid's coaster before anyone else might seem nice to some, it's not going to help that much, as it's just going to make the queue get incredible long and ridiculous before the park even officially opens anyway.
Also, from experience of doing rope drop / EE on both sides of the pond (Universal and Disney), it doesn't take long for a queue to back up within minutes of it opening if you're not the absolute first few in line. The only difference is that you're waiting sooner in the day rather than later. Which is why whenever there is a "big ride" that I want to go on, I do it last part of the evening while most of the people are watching shows, or left for the evening.