Clamps bend whether they be Bessie or elcheapo HFs they bend. That is part
of the clamping power of clamps that they bend and create tension in the
clamp. The amount of bend depends on the type and length of the clamp.
Take a bar/pipe clamp and tighten it just enough to barely hold, draw a line
along the bar/pipe, tighten the clamp and watch the deflection from the
line. If a clamp bends too much to use it is either too tight or the wrong
clamp for the job
No disrespect intended to those who say 1/2 inch clamps bend under
use, but I've not had that experience.

The clamping force necessary to edge glue boards together isn't
anywhere near the amount exerted by 1/2" clamps, so in that
application 3/4" clamps are overkill.

I suppose it's possible to bend 1/2 inch clamps by yoinking hard
enough on them to try to straighten badly out-of-square casework
carcasses, but before I loaded up on 3/4 inch clamps I think I'd spend
the time adjusting my machinery and my technique so that the joints
I'm gluing up are square to begin with.