There are definitely some things to consider before just doing it, that's for sure. Also, it's definitely not a new method and there's a lot of people I've read/heard about getting caught growing in corn. Most of the time, similar to your example, it's due to carelessness or greed.
I also appreciate your stance on being respectful of other's property; for a lot people that's not even a thought that crosses their mind. I feel that whatever your decision is, it's important to only do what your capable of & comfortable with. If you can justify the farmer losing 10 ears of corn so you can have a years-worth of smoke, I understand. If not, I understand that too. It really depends on the locale and the situation. As a quick mention, there are also (usually) very small bare patches in most larger fields from when the seed-spreaders run out, skip a beat, or temporarily clog for a split-second when they're sowing the seed early in the season. Those bare spots can also be utilized without having to pull a single stalk.
Thanks a lot for your valuable input, and thanks for reading. :)