[bulletsvshumans]

Maybe the glut of conventional food leaves the prospect of eating their compatriots less appetizing.

[thaumasiotes]

Probably not; these aren't closely related spiders. It would be like a human eating a monkey, which is something humans like doing.

But if the smaller spiders can fight back at all, it might well make that battle less appealing.

[eimrine]

Spider fight is wrestling about who does the one shot one hit, they do not hit or puncture in other in order to make just a mechanical damage.