Probably, it is ...
Front suspension, lower control arms ... the rear compliance bushings are the actual things that are showing cracking. They can show surface cracking while not actually having problems. But they can also wear enough to cause alignment or driving stability issues.
Honda does not sell those bushings separately.
So of course, if the dealer will only use Honda Genuine parts, they have no option other than to replace the whole control arm.
I replaced those bushings recently on my own car (at 145k miles, bushings were not too bad) and my friend's 2006 (same bushings; at almost 200k, he definitely needed them), bought at RockAuto.com for about $10 each.
If you've done anything like this before, the ONLY thing tough about it is to go and get yourself a bushing press of sufficient size. I made a failed research and development project in trying to rent those tools for free at various local auto parts stores, before giving up and buying a full bushing press set on eBay, which made the job as easy as it should be. The $80 capital investment was easier to justify, knowing that I'd be immediately using it on both mine and my friend's cars. And that set is pretty amazing - 5 spindles and about 22 cups, all with 5mm wall.
Those bushings have a diameter of 74mm, so you need one press cup with an ID slightly bigger than that, and another cup with an OD of slightly less than that. This was all done with no need to buy tools back on my '99 Odyssey, which had 65mm bushings; for that size, the standard free-rental tools from PepBoys, etc. will do it.
The front bushings in the control arms never wear out and don't need to be replaced. My ball joints were in great shape, so I renewed the grease in them and left them in there.
Couple of things to get right are:
- press in the new bushings with the same orientation as the originals. They are not rotationally symmetric.
- torque bushing screws with the vehicle suspension at nominal loaded geometry. (same as for almost all suspension bushings)
One bonus surprise I found was that replacing the bushings fixed my alignment to perfectly straight again. Before the replacement, it had been pulling to the right a little. So I crossed the alignment off the todo list, which was an unexpected gift.