Short answer: use
compost as mulch
I made a lasagna bed here in Taiwan where we have huge MONSTER snails. 2 weeks later they arrived in force and pretty much F'ed S up. But I noticed that 2 months later, after the bed had broken down into finer particles, it was no longer all that attractive to them anymore, like they had been replaced by worms. That led me to the idea that for those of us with lots of slug and snail pressure, was can still mulch but we should be using material that is at least half way composted so as not to provide habitat to the little guys.
There is another alternative to this that would mean less labor but proportionately more slugs: mulch rotation. If we are going to use thick mulch, we should only mulch about half of our beds so that the ones that are already mulched have time to break down. That means that half the garden is slug habitat but the other half is not. With the prime real estate being constantly moved, the slugs don't have perennial breeding grounds. By the time slug eggs hatch, there is little protection from predators anymore.
Will this second method also deny Housing Justice to slug predators? I don't think so. Slugs move relatively slowly and cannot quickly move from one shelter to another. Wolf spiders and beetles move much faster and can likely migrate to the next mulched area. Birds, snakes, lizards and frogs wont be using the mulch for habitat anyways.