There may be a very valid military reason a B-1 was used to demolish some abandoned buildings instead of a bulldozer, but to a civilian like me it looks like very expensive make work. And that makes the Air Force look sort of pathetic, silly even. That makes it hard for people to spend the money that will be needed to enable the Air Force to do its job in the next war comin'.
I can agree that having some big D9 dozers are real handy at reducing built up terrain are real handy, but they are often hard to come by because they are elsewhere in theater, cannot be transported out to site, or the environment is non-permissive and forces cannot be spared to secure them or their movement- having been on the wanting end of heavy equipment to do things for me - you might end up at the back of a long line. Contracting locals might be an option - provided they will come to your neighborhood - even if the money is good, it may not be enough to convince them their will be no reprisals.

I suppose sappers might be employed - but then your going to get allot of rubble that might be just as well used as the original structures - but you'll have some happy sappers

On the use of air and rocket delivered munitions - I think there are some benefits that go beyond straight justification of support:

1) You demonstrate a capability that nobody else possesses to your enemies, friends and uncommitted neighbors that hopefully provides a perception that with little coordination or risk to the good guys or civilians, you can reach out and deny the enemy cover and concealment and make another attack on the COP/FOB a much riskier venture.

2) Air ground coordination takes practice for when you may really need it - if we were not doing under those conditions, we'd still need to drop real bombs (or inert blue ones) somewhere to maintain that proficiency for when we do need it.

I think in this case we got a two-fer.

I agree with your rational as to why we need an Air Force, but as a typical knuckle dragger I'd like to expand it -

Nobody will think about "Air Superiority" quite like an Air Force - so not just about destroying the other guy's AF, but denying the other guy air superiority, and providing the CDR (be they a Regional COCOM, JTF, sub-unified command type, etc.) the advantages and options that gaining and retaining air superiority can provide. The trick is to get everybody to understand the problem and conditions at hand in order to make the most of resources available.

Best Regards, Rob