I'm the kind of GM who doesn't like the particular type of setting that 'consistency with the rules' tends to produce. Personally, I just don't like it when it only makes sense that every city worth its salt has Zone of Truth cast during important trials, or when every smart king is wearing Glamoured Deathward Mithral Full Plate of Heavy Fortification at all times, or when a foe's ability to fly or summon demons or teleport inside is an important factor to consider in fortress design.
It's just...not what I want. It takes things too far away from the sort of fantasy I'm really after:
Good guys with swords/spears/bows fighting bad guys with swords/spears/bows (and sometimes evil sorcerers and terrifying monsters), while traveling through dark forests, chasing thieves through sprawling cities, exploring ancient ruins, and sneaking into castles.
To put it simply, I want Epic Medieval Fantasy...
Epic: world-shaking events, true heroes and villains, warfare, etc.
Medieval: castles, armor, swords, bows, knights, peasants, kings, guilds, etc.
Fantasy: a 'made up' setting; magic to some extent; fate and destiny; poetic justice, etc.
Anyway, the point is, I want a setting that's only one or two steps away from a 'realistic' medieval one. If you try to keep the setting consistent with the rules of D&D, the level of magic produces something too...divergent...for my liking. In the same way, I don't like ninjas, or dinosaurs, or robots, or trains, or modern cultural phenomenons in my settings.
All of that said, I long ago gave up on trying to 'normalize' D&D, and switched over to Grim Tales...I came to the conclusion that there's no point in trying to make D&D something it's not, when there are so many better systems for that sort of stuff. Oh, and I'm perfectly happy playing in a 'standard' D&D setting...it's just having to change my setting in a way I don't like to make sense in the context of the rules that I don't like.