I just about guarantee a better price online than any gun shop. In which case you have to factor in sales tax. Versus how much time are you spending driving around to gun shops looking for a box? How much gas are you burning? I have four boxes of ammo in my cart at Midway right now, for one of those unpopular chamberings, totaling $144. Shipping is $14. Even if the local shop could match their price, which they can't because they don't carry it, it'd be $14 just in sales tax. Buy online and there are no wasted trips.
If I gauged my purchases according to the ammo and components I could source locally, I'd have to cut my collection by 3/4's and would be able to do virtually no cast bullet shooting. I sure as hell wouldn't be looking at 9.3's!
I have done all that; a typical MINIMUM shipping of $12 ~ 16 eats up your savings pretty fast.
I don't drive all over - I call - much cheaper than gas.
And I won't make a large purchase the first time - found too many loads my gun didn't care for.
However, once I find a good load, then I'll stock up