I agree in a way, but in all these years I've never slipped on BBs in any significant way (maybe through good tread selection) and there are a crap ton of hobbies that involve moving around outside i.e. where there is rain and wet grass/slippy mud/smooth concrete. Outdoor airsoft included of course. So I don't think slippery surfaces are even close to unique to airsoft and I'd also primarily regard that as an argument for good sole pattern choice, not for large/heavy boots. Tread prevents you falling over in the first place, the boot concept is about preventing ankle injury once you've fallen over, but as mentioned you're entirely likely to incur injury to plenty of places other than the ankle by falling over. Again, there's good boots, not against the idea of them, but I don't find or believe they're quite as vital as some people might think that's all.