Ideally, you would do both. Cameras to help justify the cost of infrastructure, and Wifi APs to enable additional sources of revenue like captive portal advert

Ideally, you would do both. Cameras to help justify the cost of infrastructure, and Wifi APs to enable additional sources of revenue like captive portal advertising. Not to mention the general economic benefit of offering such Wifi to smart phone users (aka shoppers in the local business districts).