You are correct, they are virtually identical.
The same kit goes for $67.99 at newegg.com, so I am guessing this is partially because of tigerdirect. Also the first set is $44.99 with a $20.00 rebate. So the difference between $67.99 and $44.99 doesn't seem as drastic. But honestly I agree with you, $24.99 vs $99.99... something seems off.
Still even $67.99 seems a little steep for 4GB, DDR3, CAS8, 1600MHz. Oddly enough Kingston has a kit on newegg with the same specs for $82.99, so go figure.
These things happen a lot, some companies charge a lot more for the same product. Sometimes it is because they are higher quality, and other times (like this one for instance) it doesn't make sense to me.