Me and my wife always fly business if the flight is more than an hour, I think it's totally worth it.

For one thing, im a big dude, the difference in comfort is more than slight when you're 6'4". Business vs economy is the difference between arriving at my destination ready to start the vacation or sore, tired, and grumpy.

We only fly maybe once or twice a year, so spending the extra cash on business means we can enjoy our limited vacation time from start to finish, instead of spending the first and last portions miserable

You may as well say you don't understand why people waste money on hotels and restaurants on vacations when there are hostels and fast food available. The point of a vacation is to enjoy your self - and so if you can afford them, luxuries arent a waste at all