Not more expensive
The up front price of LEDs is higher but the operating cost is far lower because the last about 20 times longer and use about 80% less energy. A good analogy is a magazine subscription:
1 issue: $6.00
12 issues: $25.00
Wow, $25 for a magazine? But which is higher? It depends, of course - are you going to buy more than one? At four, you hit the crossover. At 12, you are way ahead. It works exactly the same with LEDs.
75W Halogen: 2,500 hours, $8.00 = $437.00 for 10 years (bulb replacements and energy.
17W LED: 50,000 hours, $50 = $130 for 10 years (no bulb replacement, 78% less energy)
This is an average - varies by amount of time used/day and cost per KwH (which isn't going down).
So, which costs more? The LED almost always COSTS less, though the price is higher.