The benefit to a business having WiFi is that it brings customers in. There is no benefit to those that don't utilize it, but as I said, the potential risks (to those bystanders) is outweighed by the rewards (those that do use it)
Now, you could argue that a business could benefit the same way by allowing vaping, but that's currently not the case. In a few years, maybe, but not now. The average business would turn off more customers than it would gain by allowing vaping - which is the main reason for not allowing vaping, not health risks.
If I can argue that a business can benefit the same way, but is not the case, then what is the purpose of suggesting I could argue that? I'm confused on that. I think it is same thing and same benefit to business, while plausibly same risk/lack of benefit to bystanders. It may not be same amount/percentage of customers that are attracted, but I think I speak for most vapers when I say if a business allowed it, it would bring in more customers. I feel you are assuming there would be a loss of customers in that process, thus arguing that the loss of non-vaping customers would (far) outweigh the influx of vaping customers.
And I fully believe right now, and for say last couple years, it would bring in more customers than it would lose. Get a few more anti-vaping articles, reports and sensationalized news stories that make it easy to shame vapers in society, and I'd agree that it would likely be more customers lost than those coming in. Yet, I don't see that magically getting better in next few years, especially if, or as, usage bans become widespread. The shaming factor is undoubtedly going to go up, even if science comes along as says what we all already pretty much think/know.
For there to be a significant loss in customers, now or at any point, the second-hand vapor myth must be in full gear. Non-vapers must believe that standing within 5 feet of a vapor will result in undue harm and harm akin to SHS. Perhaps they'll come to know it isn't exactly the same, but is close enough that if you are near a vaper, it is going to affect you adversely and thus best to avoid all locations where vapers are present.
So, not really a nuisance, but a situation where unknown risks are perpetuated by myths spun into 'currently known facts' from anti-vapers. If same thing was done via Wifi and myths of unknown factors were spun into 'danger Will Robinson, danger!' I'm thinking majority of businesses would go route of, "sorry, no more Wifi at this location" because of risks to bystanders AND all persons present.
Instead, as it appears to me, Wifi was allowed to get over a hurdle that vaping is currently being denied for really no other reason than to perpetuate a myth and manipulate mass perception.
As I have vaped (often) within 5 feet of non-vapers (who detest smoking), it is challenging to understand how majority of general public would react differently than these people who I have experience of vaping around. Yet, it certainly helps the anti cause if we vapers believe that no one wants to be exposed to second hand vapor, with all its unknown risks and currently known level of relative harmlessness.