I have run into individual IPSC shooters that cannot stand the idea of IDPA. On multiple occasions when shooting IPSC matches, I have run into anything from snide remarks to outright hostility. For what it's worth, I don't show up making comments about the "superiority of IDPA vs. IPSC" or anything else of that nature. I go to shoot. I view IPSC stages as having more of a carnival feel to them than most IDPA stages, (I did say most, not all). That doesn't make the skill set neccesary to complete the stage any more or less stringent. I feel pretty confident that if you can clean a Texas Star in 5 shots rapidly, you can hit a moving bad guy paper target, or for that matter, a badguy ducking in and out of cover.
At one point and time, when I had the time to shoot matches every weekend I had quite a few discussions with some of the Area 6 bigwigs here in Ga. These were good discussions, none of the low blows that I have experienced from some of the more militant members.
To be fair, I have seen IDPA shooters start in on IPSC shooters that were giving an IDPA match a try. If I have the opportunity, I try to nip that in the bud. It happens in both sports, there are some that cannot let things go at the "good-natured ribbing" line and have to cross deep into the "you're starting to piss me off" territory. People are people, no matter what sport or hobby they compete in. There's always a certain amount of "mine's better than yours".
Wheeler