Not sure vaping is same as someone smoking, but if its banned its banned and people should follow the rules. You get the little disposable vapes that give off hardly any vapour, then you have the massive chargeable ones that look like a steam train and the 'smoke' seems to linger but still, i'd sooner sit surrounded by 1000 people vaping than 1 person smoking, the smell of that is absolutely horrendous nevermind the effects of passive smoking.
Still, rules are rules and if people can't hang about til HT for a vape/cigarette they shouldn't be coming to the football unfortunately. Not sure they'd vape/smoke in the cinema or during their kids school play? I haven't seen anyone drinking in the stands for a long time but personally i think they'll introduce some new rules/regulations on the sale of alcohol at the football soon surrounding something like no sales 10-15mins before KO, no sales at HT etc to try to keep that risk down, clubs won't like it but i feel the authorities are going to head down that route.