Actually I don't quite understand the uproar unlimited ammo regularly creates. Most shooters (survival and tactical shooters aside) already have unlimited ammo, i.e. they throw so much ammo at you, it might as well be unlimited.
And as a side note, the way ammo is handled now makes games damn predictable. I still remember HL2, where you pretty much knew in advance what's going to happen, just by the ammo that dropped.
I'm not going to go as far as Mamoulian in condemning other shooters, but the Battlefield series has always been a very different type of FPS. It is slower paced, more strategic, and it has always been quite rewarding for me to survive for long stretches in a battle, relying on ammo dumps and medics to recover after a fire fight.
Most shooters have quick deaths, quick respawns, and maps that are small enough to get back into the fight immediately.