The "88" was relatively rare compared to the 20mm and 37mm guns, but more common than the 105mm "heavy" AA guns, which were mostly entrenched in semi-permanent locations. Even heavier AA guns existed in small numbers, but lacked carriages for portability, unlike the 88 and 105. Tow vehicles were one of the main limitations. A Flak battery attached to a division would have a few 88s to protect the larger formation from high-altitude bombers, and a host of lighter AA to distribute among the various companies and battalions for more localized defense against strafing and dive bombing attacks.
The merits of the 88 as an AT gun were not helped by the giant rotating carriage and gun shield. The huge silhouette made it an obvious target for anything with the range to shoot at it, or to call in artillery against it. Late in the war, a gun carriage specifically for AT applications (with a PAK designation, rather than FLAK) was developed (besides the Tiger tank and heavy TDs), but only deployed in small numbers. Most of the 88s remained primarily as AA guns.