More things I wonder...

[Red Wizard]

If Barret and Dyne are the only ones with gun arms, why does every weapon shop sell gun arm accessories?

If people who die become part of the lifestream, and mako is lifestream, and materia is processed mako, does Aeris become a materia at some point?

What the heck was that cannon at Junon pointed at anyway? And why would they have such a weapon?

How the heck is Shinra able to make a vehicle that uses only ONE cylinder? (seen in FMV at Shinra Building)

Also, how did Turtle's Paradise (in Wutai) get to advertise at Shinra HQ when these two just recently went to war?

What the heck was Yuffie going to do with all that materia anyway? Did she actually have a plan other than sell it off and make money?

In the Honeybee Inn, when Cloud sees himself and talks to himself... is this ever explained? What was actually going on?

 

[Artemisia]

If Barret and Dyne are the only ones with gun arms, why does every weapon shop sell gun arm accessories?

Why does every weapon shop sell magic combs and megaphones? I don't see anyone else using them as weapons.

If people who die become part of the lifestream, and mako is lifestream, and materia is processed mako, does Aeris become a materia at some point?

The souls of the Cetra function differently within the Lifestream, they retain a certain sentience whereas normal humans and other beings "dissolve" into the collective. So yeah, that Fire materia you're mastering could contain bits of your dog and Uncle Bob's thought processes. Who knows?

What the heck was that cannon at Junon pointed at anyway? And why would they have such a weapon?

I think I remember hearing somewhere in the story that Shinra were a weapons manufacturing company before they discovered Mako. They probably developed weapons during that war with Wutai that no one talks about. An attack by sea would warrant the use of a cannon to keep invading enemy ships at bay. That's why Junon town is virtually obsolete when FFVII takes place - war's over, no use anymore.

How the heck is Shinra able to make a vehicle that uses only ONE cylinder? (seen in FMV at Shinra Building)

I know NOTHING about vehicles and cylinders

Also, how did Turtle's Paradise (in Wutai) get to advertise at Shinra HQ when these two just recently went to war?

The war with Wutai ended at least 5 years before the events of FFVII, maybe even further back than that. Shinra don't seem to have any problem with Wutai as they were utterly defeated and reduced to nothing more than a tourist town. I guess they don't really care if their little bar wants to advertise in a building on the other side of the world. Square logic ftw.

What the heck was Yuffie going to do with all that materia anyway? Did she actually have a plan other than sell it off and make money?

She's an angsty self-centered 16 year old. I think the answer is clear.

In the Honeybee Inn, when Cloud sees himself and talks to himself... is this ever explained? What was actually going on?

This is actually a very valid question. The room is labelled the "@#$%" room which I can only imagine is the room reserved for, well, @#$%ing. I honestly cannot think of an explanation for Cloud's little freak-out in there, as there is nothing to trigger his memories like in the Reactors. Hence why I always go in the Group Room, it's funnier and makes just as little sense