Beating your average 40k player is easy since this game doesn't really draw people who are looking for a serious challenge on the table top. If you're looking for game that supports two players bringing their A game in a serious test of skills, you invested in the wrong game.
Competitive 40k is laughable based upon how flawed the rules are and the lack of any real equal footing between armies.
Based on my experience (one venues worth of 40k players over years) this is exactly right.
I can't think of a single player that has come in who simply and strictly wants to win above all else, all of the time. There are certainly degrees to which people are competitive which vary day-to-day, opponent-to-opponent, or event-to-event but even the most competitive of the bunch screw around more than not.
All of the tournaments we've run over the past year or two have been absent a large percentage of our "regular" or "core" group of 40k players. Using the last Doubles event as an example, I can think of at least 10 people off the top that didn't play because they dislike any sort of "competitive" 40k. Some of them are probably best suited for it too.
To the point about a casual crowd creating a stagnant community: I can promise you the opposite is true. I've seen it time after time, game after game, year after year, where a player or group of players come around with the intent to win, win, win. The result is always the same. The better players continually have success, the limited players (skills, models, funds, time, etc) lose more often than not, the lists, decks, pieces, cards, builds, etc remain largely the same, the players all begin to lose interest because much of what goes on is predictable and un-fun, and the game entirely (or almost entirely) evaporates over a very short period of time.
The games that tend to stick around longest and have the most success (specifically at Battleground) are the games built up around a casual, "fun for all" mind set. Players sticking to fluff or "cool ideas" will probably never run out of army composition options in 40k. If they try to compete, they are limited to what? 2, 3, or 4 different lists out of 2, 3, or 4 different codices? Half of our players have 3ish armies each of which weighs in at 2-3000+ points, there's a TON of options there and it keeps them and their opponents / friends coming back to play. This is good.
Every once in a while it's fun to run a tournament and sort of raise the stakes a bit, but as I'm sure you know, Matt, even then the majority of people that do play just throw some stuff out there that they think might be fun to use.
Maybe this last gem paints the best picture....
This years 'Ard Boyz event saw something like 4 or 5 of the 40+ regular or semi-regular 40k players sign up to play. Of the 4 or 5 I think only 2 signed up because they really wanted to compete (both advanced). The others signed up because they just wanted to play in an event.
