How many of you actually pay for a higher fare class (such as flexible) simply to get the higher fare class that entitles you to more qualifying miles.

I find myself doing this time to time and am starting to question if the miles and status is actually worth the money.

For e.g. recently I paid 400 pounds more on Turkish economy so that I get class E instead of U, this allowed me to earn about 14,500 miles on Krisflyer.

I done it simply so that I can earn the miles and requalify for status, the flexibility was never part of my concern.

What about you peeps out there, do you ever pay for higher booking class simply for the sake of miles?