he has just as much right as the ama fliers at the field to fly... lets say you both have a 50/50 chance of crashing the other guy. he crashes your plane at the field, chances are no one gets hurt and no property is damaged. what happens if you crash HIS plane. the odds of someone getting hurt or property damage is probably higher. the worst part is that he can claim he didn't realize the problem existed, but you as an AMA member are completely aware of the situation, thereby entirely more responsible should something happen.
I'm not going to keep dragging the thread off-topic, but here's my final statement. If the off-field flyer is an AMA member, NO, he does not have as much right to fly as the people at the field--it's called intentional interference. If he flies within the prescribed limit of the sanctioned AMA field without a frequency sharing agreement, he is in violation of AMA rules. He knows the field is there and has communicated with the club, how can he claim he didn't realize the problem existed? Unless this person has a disability preventing them from travelling the whole 3 miles to the field, flying at home and causing this problem is just SELFISH! If the flyer is not an AMA member then he only has to comply with FCC regs, but it is still clear that he knows the conflict exists. I just don't understand why anyone would want to be in that position.