It's not limited to 33'...

but you're right they won't work like in the wilderness, unless someone with an apple device is nearby.

My son-in-law and I tested mine about a year ago and found it ½ mile away with no other device within that distance.

I think they'd work well like in a city, or even in the country if homes are not VERY far apart. But all this said:

Pretty sure they make devices specifically for this that would bee much better.