You need to put an address in India on the visa form so if you have a visa you by default have the accommodation address.
I'm sure this is a requirement not just for India but for many other places in the world too, it certainly is for Jamaica, but as I've said you can't have the Indian visa without the address so all roads lead to rome.
Sounds to me like there's a jobs worth at large at the airport though and if they've been told to stop people travelling unless they can prove an address then I'd take some proof just in case.
Remember airlines over book so they might be using this as a tool to off load passengers without having to compensate them.