Eventually someone with far more mechanical knowledge than myself will chime in on this thread. Until that time, however, I would offer the opinion that there is no such thing as A 30,000 mile service. Rather, there is a shop's version of what they wish to call a 30,000 mile service.
Assuming you have no desire to work on cars nor the experience to do so (my situation), your best bet is to specify these types of services a la carte to avoid the work which is simply not necessary. Besides lubricating hinges and changing oil, Honda specifies that by 30k miles, only inspections, oil changes, and air filters (engine and cabin) are required. I wouldn't know a bad brake hose if you were whipping me with one, so I will specifically ask the mechanic to perform the inspections specified by Honda, but I will forego the parts replacements and services not specified by the people that built the car.
Besides the inspections, they are simply performing a bunch of busy work that isn't required. Its wasteful at best and, at worst, can result in damage or wear (opening valve covers, disturbing gaskets, losing tiny parts, stripping threads, etc.). My Honda dealer specifies a 30,000 mile service that includes changing the spark plugs, fuel filter, differential fluid, coolant, and brake fluid.
Honda's severe maintenance schedule specifies 110,000 for plugs, 60,000 for differential fluid, 120,000 miles for coolant, and 3 years, regardless of mileage, for brake fluid. My dealer also specifies "valve adjustment" every 5,000 miles, and Honda requires a 110,000 mile evaluation, with adjustment only if noisy. My very reputable independent shop has a similar wasteful menu.
In short, NEVER specify a generic 30,000 mile service. No such animal exists according to Honda. Specify the individual items which require service (page 153 of my manual).