He does market his software, and practices everything he preaches on his own software too. But let's look at some numbers.

Let's say that Patrick's techniques can increase profits by 10% compared to an "unoptimized" website. If the bingo card business is worth $X0,000, by selling his own products on optimized webpages Patrick makes an extra $X,000.

If instead Patrick consults for a company that does $X0,000,000 his techniques are now worth $X,000,000. If he gets a percentage of those new profits, he is doing much better than if he had sold more of his own product.

Since creating a business which does $X0,000,000 in sales is hard, Patrick can make better use of his time by finding those existing companies and offering his services that by selling more of his (comparatively low value) product himself.