How do FF miles affect the price of air tickes?

[Forrest Walker]

I am climbing up the tier level of my frequently used airline. I go out of my way to fly this airline just to accumulate miles. A review of my status alarmed me. It seems that if I search for and get a great price for my flight I get less miles than if I cannot get a good deal. In fact, on a recent flight, they said my "Cabin Class" way H, so I only got 50% of the miles. I am now on a flight where I did not get a good deal and my "cabin class" is Y, so I get 150% of the miles. I.E. on a 5000 mile trip I would only get 2500 miles credited if I pay a hundred dollars less, where if I pay "full fare" I get 7500 miles.  Is this common these days or is my carrier whacked?

[Anil]

Your carrier is whacked. I know that DL the sLUTty fares get 100% and YBM and higher 150%.

[Candice Sabatini]

Your carrier is whacked and sounds like one of the foreign carriers.  As far as I know, all the US domestic airlines give you one mile for every BIS (butt in seat) mile flown.  That said, I know that AA does a points vs miles thing, where if you pay a higher price you get more  points, yet full miles.  The points aren't real miles, they're just a way to get to the status level faster, but they don't affect your mileage bank.  So, IOW, if you fly NY to LA, on a discounted fare you'll get 2475 miles - these are both EQM's and bank miles but you'll get less points (half I think)  If you pay a higher fare, you'll get the same EQM's amd bank miles, but you'll get more points.  So to reach your status tier level, it's a race between miles and pointsand whichever one gets to the tier faster gives you the status. I honestly I think is far.  But it does not affect how many miles you get.

I don't know if any of the other US airlines do this as I'm an AA flyer.

[Tony Abreu]

I think you are talking about Qatar Airway's QMiles on Privilege Club.

Booking     Qmiles
Class        Accrual
-----------     -----------
Y                  150%
B, L, M, Q, K 100%
G                   75%
H, V, T, W       50%

There are also Asian airlines that do not give you 100% credit on cheap booking classes.
But, what really matters is how many miles or points you need to get a free flight to where you want to go.

[Candice Sabatini]

I think that BA (British Airways) has a similar system to Qatar where discounted tickets don't get the full mileage flown.

As I said in my initial post, it's only the foreign carriers that do this.