People generally look at magic / sorcery / witchcraft as dangerous, unpredictable, corrupting, or unnatural / evil (cf Bible, Shakespear, DragonLance... even LotR). That's what's written into DCC, I think.
Look at it this way:
One guy makes a tool that shoots a missile at a high rate of speed, which will pierce flesh and most, if not all, armor, causing injury and very likely death. It's a crossbow. Nobody looks sideways at the user/inventor, because everybody understands what's going on with it... it's a mechanical effect. Even if it breaks, you can tell why.
Other guy summons forces that are not readily apparent to throw a missile which might cause similar injury, or it might blow up in a fireball incinerating everything in a 10' radius, or it might open a doorway to an alternate dimension full of tentacled horrors and the screams of the hungry mindless hordes of ... you get the idea.
W/r/t your LotR example, Saruman fell to corruption because he used too much magic (the Palantir, in particular). IIRC, Gandalf only uses magic like once in the Hobbit, in an emergency, and although he's portrayed in the movies as using magic here and there, particularly in defending against the Balrog, I'm not so sure that was the way it was in the book... point being, shortcutting reality is risky and it probably ought to be that way.
Any sufficiently advanced technology is indistinguishable from magic, sure, but if you don't know what you're doing, exactly... maybe that warm canister you're using to heat your sleeping bag turns out to be a tac-nuke and blows your whole village sky high. Oops.
Hamun Ry (Wiz 4)
Str 10 Agi 15 (+1) Sta 11 Per 11 Int 17 (+2) Luc 10 (Unholy House). Align: C. AC: 14. HP: 13. Melee +1, Ranged +2. Crit: d8, I. Save: Ref +5, Fort +3, Will +4.
Spells: 1: Choking Cloud, Comprehend Languages, Detect Magic (odd crystal growths), Magic Missile (mirror images), Runic Alphabet (Mortal) (ravenously hungry), Ventriloquism (rain of frogs)
2: Detect Invisible, Levitate (extremely difficult, d14), Mirror Image (20% chance to raise/lower luck by 1d3 points).
Equip: Ring of the Sand Djinn: +2 AC/saves, Invisibility for 1min/spellburn point, or unmake for great, unknown effect. Padded Armor, Longsword, Longbow, quiver w/20 steel-tipped arrows, 10 silver-tipped arrows, backpack, spellbook, quill and ink, sturdy parchment (10 sheets), 5 days rations, high leather boots, belt w/ belt pouch, gray robe, dark gray hooded cloak. Also carries 3 small mechanical toys: wind-up mouse, wooden puzzle cube, small jewelry box that plays a little tune.