I guess I haven't been on the forums long enough to see that sort of attitude. I've been in on a little of the mod discussion but it didn't seem that severe to me. I didn't see anyone claiming you HAD to have a custom 870 or some such thing for it to be any good.
In general I agree with you, there's nothing wrong with a stock riot gun as it comes from the factory. Most of the guns I've had have been stock (2 Defenders, a 500, an Ithaca 37, an 870 and that stupid SPAS). Any mods I did were minimal. I had a tritium bead on one Defender which I think was nice for a HD gun. Had a side saddle on it too which again was nice for an HD gun. Other than that, the only thing I have non-standard is a full choke in my 870 and that's because the guy I got it from had it installed. I didn't go looking for one. I personally feel quite comfortable with a stock factory riot gun. Sure, I have some preferances and there's some stuff I'd like to try but they're just items of interest, not requirements. I'd feel no better armed with a tricked out 870 than I would with a stock Mossberg to be honest. Both perform the same tactical role and perform it similarly, with or without ghostrings, etc.
I suspect that one reason folks like to putz with their shotguns is that it's cheap and easy to do. Aftermarket items for shotguns are generally a good bit cheaper than many custom pistol upgrades and most are do it yourself projects. It's more a matter of the fact that you CAN do them than that you NEED to do them. It's fun to customize a gun to your own tastes and preferances.
As to tactics discussions, I dunno. I'm not a cop, I'm not issued a shotgun in the Reserves and my HD situation is pretty basic, I'm looking at a static defense. While I'm sure learning some advanced tactics wouldn't hurt I just don't use shotguns for serious enough purposes to get really wound up over it. I feel competant with one and in my situation that's probably good enough. I'm not putting myself in a situation where I feel I need police or military tactical training on them. I'd feel disingenious talking about an issue I don't really have much experience about. Ask me about shootig milk jugs or steel plates though and I'll tell you all about that! I suspect a lot of folks here are in the same boat.
I shoot .12's a lot because I like to blast jugs and stuff wth them. I also use a pump 97 in CAS competition. Neither requires that much in the way of "tactical" training
I'm pretty fast and accurate engaging multiple targets from both sorts of practice. My shotgun times are always very good and I don't think I've missed or failed to knockdown a target yet in the year or so I've been shooting competition. I use game loads, not traploads and that's usually what I practice with too in addition to slugs and some occasional buck. In the house I use #6 or #4 shot generally. Presumably some of this practice would still carry over to a defense situation though.
I dunno, I guess I just don't get your gripe. So some people want to modify their guns. So what? Lot's of guys customize their pistols too. I don't think that the fact that you want a personalized gun or like ghost rings over a bead etc means you think it's a supergun. If people were argueing that you HAD to have those things I'd agree with you, but if just that they want them I don't get the beef. To each his own. I kinda though the whole point of the forum was to discuss firearms and what we can do with them
If you aren't seeing as much discussion of tactics here then start some posts of your own on the subject. I'm sure other's will gravitate towards them, but don't get mad because you have a forum full of gun buffs who LIKE to sit around and talk about guns! Remember, most of us here are probably enthusiests and hobbiests, not cops or soldiers. For you the interest is tactics, for some it's just the gear itself. There's nothing wrong with being in the sport just for the gadgets you know