I used to fight heavy in the SCA. It was fun. Never got any good, though, mostly because I didn't own a car. Seriously, packing that armour on transit is no picnic.
That really only happens if you get steel armour. Steel is cool and I personally prefer it, but recently more and more people get ABS (i think) plastic gear, which is lighter, cheaper and easier to manufacture.
Mine was sort of pieced together--some plastic, some boiled leather, some steel (and as far as I know, non-steel helms aren't SCA legal)--but really it's less about weight and more about volume. When you add together all the bits, it's just really unwieldy.
(There was a story about a guy who made a helm out of titanium--it was gorgeous, and when he tried walloping it a bunch with a big polearm it just scuffed when a steel helm would have dented. So he tried it out. He was a major league marshal in his kingdom, so when he regained consciousness he immediately declared titanium helms illegal for that kingdom. Y'see, the problem was it was too light. There wasn't enough inertia stopping it from moving, so if someone hit it a good hard shot the whole helm would be jolted sideways; it would just smack the wearer's head and ring their bell. Light isn't a problem for most armour as long as it distributes the impact, but for a helm that isn't good enough.)
Also, if you have an established group that you can trust, one person with a big enough car can carry gear for a lot of people.
Yes, that's very true, but I was not really in that position. There were a group of us, but we were all relatively-impoverished university students, and fighting practice was in a somewhat awkward direction. Look, just bloody trust me OK? It was aggravating as hell, if there were an easy way around it I would have used it.
Also for anyone wondering, under SCA rules, the weapons are strictly blunt, and the tips have to be either folded back, or covered with a plastic tip, as well as said tip must have three different colours, so when it inevitably falls off during combat, the marshall can spot it and call hold. (By three colours I mean white/black for the plastic tip usually + coloured duct tape + the gray of the steel although I have seen black swords.) Which, in the manga did not appear at all.
Your kingdom allows steel weapons? In the West and An Tir as far as I know it's strictly rattan--similar weight to an equivalent steel weapon, but waaay less dangerous. No edge, but doesn't splinter like most wood. So you can hit full strength with no worries. And there are elaborate rules about how to build a legal thrusting tip on a weapon. Typical broadswords didn't tend to have pokeys at all.