Chipperman:
While I do know how the RFID chips work, I've not idea just what you're doing to set things off. Note, though, that I said nothing about how the store's software works...
Still, I carry whenever I've pants on, which is all the time, for those who'd scoff, and I've had no problems anywhere, including HD, drug stores, etc.
Beyond clearly exhibiting the fact that I've a weapon on board, after 8 years in NH I've more or less gotten over the "big deal" syndrome, and would merely present the carry permit if challanged, and so wouldn't worry about screening.
'course, I'd neither buy nor return, but that's another story.
Like everybody else says, sounds like you've a tag somewhere.
As a "shall issue" state, there are many more CCW's floating around than the normal Massachusetts resident, notice the restraint exercisec here as I withold the NH abbreviation for those from the south, would suspect, and we don't seem to have any problems.