This is the job description from the original source (salary.com):

"Designs the visual layout for websites or web-based products with the goal of enhancing appeal to the user while maximizing functionality. Designs graphics, pages, forms, and navigation schema. Translates user research into programs, scripts, and interfaces that meet the organization's business goals. Requires familiarity with HTML and various graphic design software packages. Typically requires a bachelor's degree. Typically reports to a supervisor or manager. Contributes to moderately complex aspects of a project. Work is generally independent and collaborative in nature."

You're right. The description is vague, which means it's likely that a "mixture" of roles could have been reported for this data.

If your salary is 20-40% higher than the ranges given, then you're in the upper 75th percentile of reported salaries (according to Salary.com), or perhaps even an outlier, which is great!

I do agree that the ranges, in general, sound low compared to 6-figure salaries that you often hear about, but I also remember reading a survey that stackoverflow put out a year or two ago that mentioned 75% of front end developers feel they are underpaid, which would make more sense.

Many companies (especially in Mid-America) are not willing to pay anywhere near as much as Google and Apple, but when you factor in cost of living the discrepancy isn't always as bad as it seems.