I believe the old recommendation was that you could shift in and out of 4wd HIGH at up to 45mph.
As usual, your results may vary. Just like the ease of shifting Dana 20's varies from unit to unit.
For short trips your mileage loss is likely to be minimal. Out on the open highway it might be a bigger deal, but if I was traveling short distances and I knew I was going to be needing 4wd literally almost every day like the OP experiences during season it sounds like, I would leave them locked in too.
If in the summer months traction is not an issue, you can leave the hubs unlocked and simply shift to 4-wheel LOW range and use the gears rather than any real need for the front end helping.
If locked all the time, then I'd just unlock them now and then as more of an exercise for the parts and making sure they all work properly than anything else.
And while I agree that wear-and-tear and mileage is effected, it can't be too serious as it used to be, since no manufacturer currently puts free-running hubs in their 4wd vehicles that I'm aware of. For that you have to go to the aftermarket.
Dodge used axle disconnects for awhile on their solid axle setups, but I don't think they do anymore. Either that, or they're more reliable now so we don't hear about their failures as often? GM IFS setups had something as well, but not sure how that works currently.
And not sure if Ford ever did use any type of disconnect on their solid axle front ends. Just at the transfer case?
So unless you're putting tens of thousands of miles a year on your Bronco, I don't see wear and tear, or fuel economy as being the big deal it was in the seventies. It's true that the D44 in EB's (low pinion) is driving on it's coast-side, so wear is odd when compared to it's original position as a rear axle, but it's only wearing the coast side when under power. Just leaving the hubs locked would not create that situation.
Maybe with our t-cases and old-school axles it's a bigger deal. I just don't know what would have changed inside an old D44 vs a new one, or an old t-case vs a new one other than being chain drive again.
Either way, it's a very workable solution for the OP.
Paul