How much weight do boxers cut regularly?

Tacking onto OPs question, is there any coherent explanation why MMA fighters generally dehydrate and rehydrate so much more than boxers? It’s obvious that boxers are not afraid to cut weight, so why don’t they go the whole hog? I’ve wondered about this a lot but weight cutting seems to be consistently misunderstood and I’ve never heard a straight answer that makes sense.

UFC fighters like Alex Pereira or Paulo Costa are literally rehydrating 25-30lbs (185 up to 210-215) and there are similar stories throughout the divisions. You hear similar in boxing but it’s just not on the same scale. You rarely hear these UFC guys who have rehydrated 30lbs complain about being drained either (they will complain about the process, but not often that they were compromised come fight time).

 

5’10 and 175, an average boxer might drop to 154-160, some may even go as low as 147.

 

I remember in an interview that Margo walks around at 170+ and cuts down to 147.

 

Roiman Ellis usually cuts around 20 or so pounds to make the limit.

 

I've also never understood why this happens now that everyone does it and there's no advantage to be gained (since you can guarantee your opponent is doing the same thing). It can't be good for long term health. Same day weigh ins would make lots more sense, as it would stay fair to all with surely less risk to the fighters.