Well if they can't raise cash somehow from their service then they may very well fuck off and die. Then they won't be there anymore, and we all lose something then.
Free to use isn't the same as cost free, and without funding who's going to pay their bills? This isn't necessarily a good way of monetising their business, but I can't see a paid for service working commercially for IFTTT either.
The way things are going our data will have been scrapped for advertising hints by so many outfits on its way to us there'll be little point in it being private. Might as well send it en clair and let commercial advertisers tap our home Internet connection... Would that really be any different to how we use and pay for Google, IFTTT, Facebook, etc, etc?
Amazon, Netflix, etc are different - there's a good reason to give them actual money. Thus they could offer Google-like or IFTTT-like services as a fringe benefit without any of the nasty intrusion. That sounds pretty appealing to me.