There seem to be two separate strands here, one explicit and the other unmentioned. The explicit strand is, as you correctly note Shanna, that most people are inherently lazy and this reinforces their already restricted vocabulary. If you want this set of people as your audience it is necessary to keep everything at a 12-year-old level (arguably not just the vocabulary but the intellectual content too). If, however, one wishes to write with style, the sound and subtleties of words become predominant. Truculent is not at all the same as aggressive regardless of what an online thesaurus may claim. If I, for example, happen to use the word "luxurious" I do so in the full knowledge that its meaning has changed over time from "light-bringing" to "decadent" to today's more anodyne "expensive/pampering." If I want to make a point more memorable I may employ assonance, which requires specific word choices.
As it is, I write largely for my own entertainment and hope that anyone who chooses to read my articles will appreciate the extensive lexicon employed therein, knowing that it is purposefully and even at times artfully arranged.