Have the minimal grace of not putting straw thoughts into people's heads.
Forgive me. Analysis of motive and behaviour is part of my job and it often intrudes into my hobbies.
I don't see the appeal of an approach to roleplaying that says "look! The set is made of cardboard cutouts! Don't you ever forget that the set is made of cardboard cutouts!"
I don't really follow here. I mean, if this is a criticism of 4e it should be a criticism of fantasy roleplaying games in general.
Personally I think the criticism should be directed at players who see their characters in terms of mechanics first and story second.
And in this particular case, it's not even edition-specific. There's nothing I'm aware of in 4th edition that says that random town guards can or should range from 1st to 30th level.
It doesn't and they shouldn't. Have a look at chapter 4 of the DMG, specifically page 56. Town guards should be whatever level and role the DM deems most appropriate for the type of encounter he is building.
So if he wants an easy encounter (and it's up to the individual DM to determine whether 'x' number of guards is an easy, standard or hard encounter for PCs of 'y' level in his gameworld) then he sets the total encounter level "one or two levels lower than the party's level" (56).
The DM can build this encounter in a couple of ways - either add or subtract guards, make them minions, elites or solos, or adjust the levels. Though as the DMG says, "Monsters... more than four levels below the party's level... don't make good challenges." (57)
If you decide that in your world twenty town guards aren't just an easy challenge for your 10th level party, but are in fact no challenge at all (which is fair enough) then don't bother wasting valuable gaming time on combat. Just describe the massacre and get on with the repercussions (if there are any).
Likewise if the same 20 guards accosted your 1st level PCs. In my view of D&D, if a 1st level party doesn't (or can't) run from 20 town guards then they face more than a "hard" encounter and so I wouldn't waste time running it as a combat encounter - "The guards tackle you to the ground, beat you up, and drag you away to the cells."
You might decide that the same encounter in your world is "merely" a hard encounter and so build it as a level 5 encounter - "A hard encounter is two to four levels higher than the party's level." (56)
And some DMs in 3e had high-level "average" soldiers and citizens (not an approach I favored, but it didn't seem too rare)
I had the same problem in 3e/3.5e and wasted a lot of time trying to come up with a baseline standard for the Average Joe. I'm happy 4e has solved it all through changing the way I look at the game.
Additionally, thinking and talking about "what if" with imaginary constructs is part of the fun of roleplaying. If you don't get to do that, why not just hammer on things in the garage, or something? No self-indulgence there!
Mate, if you haven't noticed I'm here thinking and talking about D&D too. I'm just saying if that's all people are going to do with the game they shouldn't complain when it is reworked to make it easier to play and
especially to DM.