valve seal service is part of regular maintenance, so is checking and adjusting the valve bucket clearance - If you dont do this your engine will keep on feeling tardy and will consume a lot of oil too.
You have no idea how ratty the fuel is all over Northern America, the ethanol blended fuel sips moisture and gets waterlogged, it gives pathetic mileage too. Couple that with expensive labor and you get a very bad recipe for disaster. In such times if you follow manufacturer recommendation for service the engine will work correctly. If you choose to have it repaired with hammer/chisel/cheater pipe etc. thats not valid reason that the availability is bad.
e.g. recently you replaced your radiator with a junk one, in most other countries they would not touch a junk radiator because it is known to become brittle and may crack at the worst of times. So who chose the wrong path, anyway - like dms said your 5AFE engine was picked up used and you chose to risk running it without knowing its usage or service history. You are now seeing the required upcoming maintenance in the form of oil consumption.
